Tasks Details
easy
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:
function 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] = 5the 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)].
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Solution
Programming language used JavaScript
Total time used 4 minutes
Effective time used 4 minutes
Notes
not defined yet
Task timeline
Code: 08:32:19 UTC,
java,
autosave
Code: 08:34:40 UTC,
js,
verify,
result: Failed
Analysis
expand all
Example tests
1.
0.072 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, integer expected, 'undefined' found Perhaps you are missing a 'return'?stdout:
[ 0, 0, 0, 0, 0 ]
Code: 08:35:42 UTC,
js,
autosave
Code: 08:35:45 UTC,
js,
verify,
result: Passed
Analysis
Code: 08:35:52 UTC,
js,
verify,
result: Passed
Analysis
Code: 08:35:55 UTC,
js,
final,
score: 
100
Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N) or O(N * log(N))
expand all
Correctness tests
1.
0.068 s
OK
2.
0.072 s
OK
1.
0.068 s
OK
2.
0.072 s
OK
1.
0.068 s
OK
2.
0.068 s
OK
1.
0.072 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
1.
0.072 s
OK
expand all
Performance tests
1.
0.084 s
OK
1.
0.084 s
OK
1.
0.112 s
OK
2.
0.100 s
OK
3.
0.100 s
OK
1.
0.112 s
OK
1.
0.104 s
OK