Tasks Details
easy
1.
PermCheck
Check whether array A is a permutation.
Task Score
100%
Correctness
100%
Performance
100%
A non-empty array A consisting of N integers is given.
A permutation is a sequence containing each element from 1 to N once, and only once.
For example, array A such that:
A[0] = 4 A[1] = 1 A[2] = 3 A[3] = 2is a permutation, but array A such that:
A[0] = 4 A[1] = 1 A[2] = 3is not a permutation, because value 2 is missing.
The goal is to check whether array A is a permutation.
Write a function:
class Solution { public int solution(int[] A); }
that, given an array A, returns 1 if array A is a permutation and 0 if it is not.
For example, given array A such that:
A[0] = 4 A[1] = 1 A[2] = 3 A[3] = 2the function should return 1.
Given array A such that:
A[0] = 4 A[1] = 1 A[2] = 3the function should return 0.
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..1,000,000,000].
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Solution
Programming language used C#
Time spent on task 2 minutes
Notes
not defined yet
Analysis
Analysis
Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N) or O(N * log(N))
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Correctness tests
1.
0.059 s
OK
2.
0.059 s
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1.
0.059 s
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2.
0.058 s
OK
1.
0.061 s
OK
2.
0.061 s
OK
3.
0.061 s
OK
4.
0.061 s
OK
1.
0.061 s
OK
2.
0.061 s
OK
3.
0.059 s
OK
4.
0.059 s
OK
1.
0.061 s
OK
2.
0.061 s
OK
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Performance tests
1.
0.065 s
OK
2.
0.068 s
OK
1.
0.099 s
OK
2.
0.104 s
OK
1.
0.108 s
OK
2.
0.112 s
OK
1.
0.099 s
OK
2.
0.098 s
OK
1.
0.062 s
OK
2.
0.087 s
OK
3.
0.060 s
OK