Test results - Codility

Tasks Details

easy

1. PermMissingElem

Find the missing element in a given permutation.

Task Score

100%

Correctness

100%

Performance

100%

An array A consisting of N different integers is given. The array contains integers in the range [1..(N + 1)], which means that exactly one element is missing.

Your goal is to find that missing element.

Write a function:

class Solution { public int solution(int[] A); }

that, given an array A, returns the value of the missing element.

For example, given array A such that:

A[0] = 2 A[1] = 3 A[2] = 1 A[3] = 5

the function should return 4, as it is the missing element.

Write an efficient algorithm for the following assumptions:

N is an integer within the range [0..100,000];

the elements of A are all distinct;

each element of array A is an integer within the range [1..(N + 1)].

Solution

Programming language used Java 21

Time spent on task 13 minutes

Notes

not defined yet

Code: 06:06:55 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
    }
}

Code: 06:07:00 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
    }
}

Code: 06:10:42 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        
    }
}

Code: 06:10:58 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 
    }
}

Code: 06:11:09 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+
    }
}

Code: 06:11:19 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 
    }
}

Code: 06:11:44 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 
    }
}

Code: 06:11:54 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
    }
}

Code: 06:12:25 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        1 2 3 5
    }
}

Code: 06:12:35 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // 11 - 
    }
}

Code: 06:13:15 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // 
    }
}

Code: 06:13:46 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        
    }
}

Code: 06:14:06 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = 
    }
}

Code: 06:14:19 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        for()
    }
}

Code: 06:14:29 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        for(int i:A){
            
        }
    }
}

Code: 06:15:08 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        
        for(int i:A){

        }
    }
}

Code: 06:15:39 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 
        for(int i:A){
            all +=i;
        }

        all += n;

        all - 
    }
}

Code: 06:16:00 UTC, java, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i:A){
            all +=i;
            sum += A[i];
        }

        all += n;

        return all - sum;
    }
}

Analysis

expand all Example tests

▶

example
example test

✘

RUNTIME ERROR
tested program terminated with exit code 1

0.023 s

RUNTIME ERROR, tested program terminated with exit code 1

stderr:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 5 out of bounds for length 4
	at Solution.solution(Solution.java:20)
	at Exec.run(exec.java:44)
	at Exec.main(exec.java:33)

Code: 06:16:47 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i:){
            all +=i;
            sum += A[i];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:16:59 UTC, java, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i=0; i < n; i++){
            all +=i;
            sum += A[i];
        }

        all += n;

        return all - sum;
    }
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -1 expected 4

0.031 s

WRONG ANSWER, got -1 expected 4

Code: 06:17:51 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i=1; i < n; i++){
            all +=i;
            sum += A[i];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:18:04 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i=1; i < n+1; i++){
            all +=i;
            sum += A[i-1];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:18:05 UTC, java, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        for(int i=1; i < n+1; i++){
            all +=i;
            sum += A[i-1];
        }

        all += n;

        return all - sum;
    }
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 3 expected 4

0.022 s

WRONG ANSWER, got 3 expected 4

Code: 06:18:30 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        for(int i=0; i < n; i++){
            all +=i;
            sum += A[i-1];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:18:42 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1;
            sum += A[i-1];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:18:52 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1; // 1,2,3,4
            sum += A[i-1];
        }

        all += n;

        return all - sum;
    }
}

Code: 06:19:02 UTC, java, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1; // 1,2,3,4
            sum += A[i-1];
        }

        all += n+1;

        return all - sum;
    }
}

Code: 06:19:10 UTC, java, verify, result: Passed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1; // 1,2,3,4
            sum += A[i];
        }

        all += n+1;

        return all - sum;
    }
}

Analysis

expand all Example tests

▶

example
example test

✔

0.023 s

Code: 06:19:37 UTC, java, verify, result: Passed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1; // 1,2,3,4
            sum += A[i];
        }

        all += n+1;

        return all - sum;
    }
}

Analysis

expand all Example tests

▶

example
example test

✔

0.023 s

Code: 06:19:43 UTC, java, final, score: 100

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // Implement your solution here
        //1 + .. N+1 = 2+3+1+5 = 11
        // 11 - x = 4 ,x = 7 
        // N이 4 1+2+3+4+5 = 15
        // 11 
        // 15-11=4
        int n = A.length;
        int all = 0;
        int sum = 0;
        // n=4
        // 0,1,2,3
        for(int i=0; i < n; i++){
            all +=i+1; // 1,2,3,4
            sum += A[i];
        }

        all += n+1;

        return all - sum;
    }
}

Analysis summary

The solution obtained perfect score.

Analysis

Detected time complexity:

O(N) or O(N * log(N))

expand all Example tests

▶

example
example test

✔

0.023 s

expand all Correctness tests

▶

empty_and_single
empty list and single element

✔

0.023 s

▶

missing_first_or_last
the first or the last element is missing

✔

0.024 s

0.023 s

▶

single
single element

✔

0.023 s

▶

double
two elements

✔

0.023 s

▶

simple
simple test

✔

0.024 s

expand all Performance tests

▶

medium1
medium test, length = ~10,000

✔

0.032 s

▶

medium2
medium test, length = ~10,000

✔

0.032 s

▶

large_range
range sequence, length = ~100,000

✔

0.122 s

0.074 s

0.071 s

▶

large1
large test, length = ~100,000

✔

0.123 s

▶

large2
large test, length = ~100,000

✔

0.082 s