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:

def solution(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 Python

Time spent on task 6 minutes

Notes

not defined yet

Code: 12:31:55 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) {
        // write your code in Java SE 8
    }
}

Code: 12:32:01 UTC, py, autosave

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# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    # write your code in Python 3.6
    pass

Code: 12:32:49 UTC, py, autosave

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        j = i+1
        if j != A[i]:
            return j
    return 1

Code: 12:33:04 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    return 1

Code: 12:33:16 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

6.0
6.0

Code: 12:33:38 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Code: 12:33:39 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

6.0
11

Code: 12:33:58 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = (n*(n-1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

6.0
11

Code: 12:34:18 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = (n*(n-1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Code: 12:34:22 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = n*(n+1)/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

10.0
11

Code: 12:34:49 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = (n*(n+1) )/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Code: 12:34:51 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.052 s

WRONG ANSWER, got 0 expected 4

stdout:

10.0
11

Code: 12:35:37 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Code: 12:35:39 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

15.0
11

Code: 12:35:49 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return 0

Code: 12:35:50 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return 0

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got 0 expected 4

0.036 s

WRONG ANSWER, got 0 expected 4

stdout:

15.0
4.0

Code: 12:35:59 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return sum_all - sum

Analysis

expand all Example tests

▶

example
example test

✘

RUNTIME ERROR
tested program terminated with exit code 1

0.036 s

RUNTIME ERROR, tested program terminated with exit code 1

stderr:

Invalid result type, int expected, <class 'float'> found.

stdout:

15.0
4.0

Code: 12:36:14 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return (sum_all - sum)

Code: 12:36:15 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return (sum_all - sum)

Analysis

expand all Example tests

▶

example
example test

✘

RUNTIME ERROR
tested program terminated with exit code 1

0.036 s

RUNTIME ERROR, tested program terminated with exit code 1

stderr:

Invalid result type, int expected, <class 'float'> found.

stdout:

15.0
4.0

Code: 12:36:35 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    print(sum_all - sum)
    return (sum_all - sum)

Analysis

expand all Example tests

▶

example
example test

✘

RUNTIME ERROR
tested program terminated with exit code 1

0.036 s

RUNTIME ERROR, tested program terminated with exit code 1

stderr:

Invalid result type, int expected, <class 'float'> found.

stdout:

15.0
4.0

Code: 12:36:48 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    r
    print(sum_all - sum)
    return (sum_all - sum)

Code: 12:37:03 UTC, py, verify, result: Failed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    ret = sum_all - sum
    print(ret)
    return (sum_all - sum)

Analysis

expand all Example tests

▶

example
example test

✘

RUNTIME ERROR
tested program terminated with exit code 1

0.036 s

RUNTIME ERROR, tested program terminated with exit code 1

stderr:

Invalid result type, int expected, <class 'float'> found.

stdout:

15.0
4.0

Code: 12:37:18 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    ret = int(sum_all - sum)
    print(ret)
    return (sum_all - sum)

Code: 12:37:23 UTC, py, verify, result: Passed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    print(sum_all)
    sum = 0
    for i in A:
        sum = sum+i
    
    ret = int(sum_all - sum)
    print(ret)
    return ret

Analysis

expand all Example tests

▶

example
example test

✔

0.036 s

stdout:

15.0
4

Code: 12:37:32 UTC, py, verify, result: Passed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    sum = 0
    for i in A:
        sum = sum+i
    
    ret = int(sum_all - sum)
    print(ret)
    return ret

Analysis

expand all Example tests

▶

example
example test

✔

0.036 s

stdout:

Code: 12:37:46 UTC, py, autosave

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    sum = 0
    for i in A:
        sum = sum+i
        
    ret = int(sum_all - sum)

    return ret

Code: 12:37:46 UTC, py, verify, result: Passed

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    sum = 0
    for i in A:
        sum = sum+i
        
    ret = int(sum_all - sum)

    return ret

Analysis

expand all Example tests

▶

example
example test

✔

0.036 s

Code: 12:37:49 UTC, py, final, score: 100

show code in pop-up

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

# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")

def solution(A):
    n = len(A)+1
    sum_all = (int)(n*(n+1))/2
    sum = 0
    for i in A:
        sum = sum+i
        
    ret = int(sum_all - sum)

    return ret

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

✔

0.036 s

expand all Correctness tests

▶

empty_and_single
empty list and single element

✔

0.036 s

▶

missing_first_or_last
the first or the last element is missing

✔

0.036 s

▶

single
single element

✔

0.036 s

▶

double
two elements

✔

0.036 s

▶

simple
simple test

✔

0.036 s

expand all Performance tests

▶

medium1
medium test, length = ~10,000

✔

0.044 s

▶

medium2
medium test, length = ~10,000

✔

0.044 s

▶

large_range
range sequence, length = ~100,000

✔

0.136 s

0.084 s

▶

large1
large test, length = ~100,000

✔

0.140 s

▶

large2
large test, length = ~100,000

✔

0.100 s