Test results - Codility

Tasks Details

medium

1. MissingInteger

Find the smallest positive integer that does not occur in a given sequence.

Task Score

100%

Correctness

100%

Performance

100%

This is a demo task.

Write a function:

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

that, given an array A of N integers, returns the smallest positive integer (greater than 0) that does not occur in A.

For example, given A = [1, 3, 6, 4, 1, 2], the function should return 5.

Given A = [1, 2, 3], the function should return 4.

Given A = [−1, −3], the function should return 1.

Write an efficient algorithm for the following assumptions:

N is an integer within the range [1..100,000];

each element of array A is an integer within the range [−1,000,000..1,000,000].

Solution

Programming language used Java 21

Time spent on task 14 minutes

Notes

not defined yet

Code: 10:03:04 UTC, java, autosave

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// 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: 10:03:34 UTC, java, autosave

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// 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) {
        Set<Integer> set = new HashSet<>();
        for ()
    }
}

Code: 10:03:59 UTC, java, autosave

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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }
        
    }
}

Code: 10:04:29 UTC, java, autosave

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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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
        }
    }
}

Code: 10:04:43 UTC, java, verify, result: Passed

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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.012 s

▶

example2
second example test

✔

0.012 s

▶

example3
third example test

✔

0.012 s

Code: 10:05:35 UTC, java, autosave

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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Code: 10:05:43 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

▶

example2
second example test

✔

0.008 s

▶

example3
third example test

✔

0.008 s

expand all User tests

▶

test_data1

✘

RUNTIME ERROR
invalid input, unexpected token at the end of input: 1

0.001 s

RUNTIME ERROR, invalid input, unexpected token at the end of input: 1

User test case 1:

[] 1, 6, 4, 2, 3, 1 ]

Code: 10:05:57 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

▶

example2
second example test

✔

0.008 s

▶

example3
third example test

✔

0.008 s

expand all User tests

▶

test_data1

✔

0.008 s

OK
function result: 5

User test case 1:

[1, 6, 4, 2, 3, 1]

Code: 10:06:17 UTC, java, autosave

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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Code: 10:06:27 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            System.out.print
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Code: 10:06:34 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            System.out.print(n + " ");
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = n + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

stdout:

1 2 3 4 6

▶

example2
second example test

✔

0.008 s

stdout:

1 2 3

▶

example3
third example test

✔

0.008 s

stdout:

-1

expand all User tests

▶

test_data1

✔

0.008 s

OK
function result: 5

stdout:

1 2 3 4 6

User test case 1:

[1, 6, 4, 2, 3, 1]

Code: 10:12:44 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            System.out.print(n + " ");
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Code: 10:13:36 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            System.out.print(n + " ");
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

stdout:

1 2 3 4 6

▶

example2
second example test

✔

0.008 s

stdout:

1 2 3

▶

example3
third example test

✔

0.008 s

stdout:

-1

expand all User tests

▶

test_data1

✔

0.008 s

OK
function result: 5

stdout:

1 2 3 4 6

User test case 1:

[1, 6, 4, 2, 3, 1]

Code: 10:14:01 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int n : set) {
            
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Code: 10:14:13 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int ignored : set) {            
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Code: 10:14:29 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 21 22 23

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int ignored : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Code: 10:15:18 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int ignored : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

▶

example2
second example test

✔

0.008 s

▶

example3
third example test

✔

0.008 s

expand all User tests

▶

test_data1

✔

0.008 s

OK
function result: 5

User test case 1:

[1, 6, 4, 2, 3, 1]

Code: 10:16:39 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int ignored : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Analysis

expand all Example tests

▶

example1
first example test

✔

0.008 s

▶

example2
second example test

✔

0.008 s

▶

example3
third example test

✔

0.008 s

expand all User tests

▶

test_data1

✔

0.008 s

OK
function result: 5

User test case 1:

[1, 6, 4, 2, 3, 1]

Code: 10:16:47 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

// 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) {
        Set<Integer> set = new HashSet<>();
        for (int n : A) {
            set.add(n);
        }

        int smallest = 1;
        for (int ignored : set) {
            if (!set.contains(smallest)) {
                return smallest;
            }
            smallest = smallest + 1;
        }
        return smallest;
    }
}

Analysis summary

The solution obtained perfect score.

Analysis

Detected time complexity:

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

expand all Example tests

▶

example1
first example test

✔

0.008 s

▶

example2
second example test

✔

0.008 s

▶

example3
third example test

✔

0.008 s

expand all Correctness tests

▶

extreme_single
a single element

✔

0.012 s

0.008 s

▶

simple
simple test

✔

0.008 s

0.012 s

▶

extreme_min_max_value
minimal and maximal values

✔

0.012 s

0.008 s

▶

positive_only
shuffled sequence of 0...100 and then 102...200

✔

0.012 s

0.008 s

▶

negative_only
shuffled sequence -100 ... -1

✔

0.008 s

expand all Performance tests

▶

medium
chaotic sequences length=10005 (with minus)

✔

0.040 s

0.032 s

0.048 s

▶

large_1
chaotic + sequence 1, 2, ..., 40000 (without minus)

✔

0.404 s

▶

large_2
shuffled sequence 1, 2, ..., 100000 (without minus)

✔

0.680 s

0.616 s

▶

large_3
chaotic + many -1, 1, 2, 3 (with minus)

✔

0.272 s