Tasks Details
easy
1.
Triangle
Determine whether a triangle can be built from a given set of edges.
Task Score
100%
Correctness
100%
Performance
100%
An array A consisting of N integers is given. A triplet (P, Q, R) is triangular if 0 ≤ P < Q < R < N and:
- A[P] + A[Q] > A[R],
- A[Q] + A[R] > A[P],
- A[R] + A[P] > A[Q].
For example, consider array A such that:
A[0] = 10 A[1] = 2 A[2] = 5 A[3] = 1 A[4] = 8 A[5] = 20Triplet (0, 2, 4) is triangular.
Write a function:
function solution(A);
that, given an array A consisting of N integers, returns 1 if there exists a triangular triplet for this array and returns 0 otherwise.
For example, given array A such that:
A[0] = 10 A[1] = 2 A[2] = 5 A[3] = 1 A[4] = 8 A[5] = 20the function should return 1, as explained above. Given array A such that:
A[0] = 10 A[1] = 50 A[2] = 5 A[3] = 1the function should return 0.
Write an efficient algorithm for the following assumptions:
- N is an integer within the range [0..100,000];
- each element of array A is an integer within the range [−2,147,483,648..2,147,483,647].
Copyright 2009–2025 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.
Solution
Programming language used JavaScript
Time spent on task 15 minutes
Notes
not defined yet
Code: 18:58:21 UTC,
java,
autosave
Code: 18:58:21 UTC,
java,
autosave
Code: 19:11:18 UTC,
js,
autosave
Code: 19:11:46 UTC,
js,
autosave
// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');
function isTriangular(P, Q, R) {
return P + Q > R && Q + R > P && R + P > Q;
}
function solution(A) {
A.sort();
for (let i = 0; i < A.length - 2; i++) {
if (isTriangular(A[i], A[i + 1], A[i + 2]) {
return 1
}
}
}
Code: 19:11:56 UTC,
js,
verify,
result: Failed
// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');
function isTriangular(P, Q, R) {
return P + Q > R && Q + R > P && R + P > Q;
}
function solution(A) {
A.sort();
for (let i = 0; i < A.length - 2; i++) {
if (isTriangular(A[i], A[i + 1], A[i + 2])) {
return 1;
}
}
return 0;
}
Analysis
Code: 19:12:12 UTC,
js,
verify,
result: Passed
// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');
function isTriangular(P, Q, R) {
return P + Q > R && Q + R > P && R + P > Q;
}
function solution(A) {
A.sort((a, b) => b - a);
for (let i = 0; i < A.length - 2; i++) {
if (isTriangular(A[i], A[i + 1], A[i + 2])) {
return 1;
}
}
return 0;
}
Analysis
Code: 19:12:21 UTC,
js,
verify,
result: Passed
// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');
function isTriangular(P, Q, R) {
return P + Q > R && Q + R > P && R + P > Q;
}
function solution(A) {
A.sort((a, b) => b - a);
for (let i = 0; i < A.length - 2; i++) {
if (isTriangular(A[i], A[i + 1], A[i + 2])) {
return 1;
}
}
return 0;
}
Analysis
Code: 19:12:23 UTC,
js,
final,
score: 
100
// you can write to stdout for debugging purposes, e.g.
// console.log('this is a debug message');
function isTriangular(P, Q, R) {
return P + Q > R && Q + R > P && R + P > Q;
}
function solution(A) {
A.sort((a, b) => b - a);
for (let i = 0; i < A.length - 2; i++) {
if (isTriangular(A[i], A[i + 1], A[i + 2])) {
return 1;
}
}
return 0;
}
Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N*log(N))
expand all
Correctness tests
1.
0.072 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.072 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.072 s
OK
2.
0.072 s
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3.
0.072 s
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4.
0.072 s
OK
5.
0.072 s
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6.
0.072 s
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1.
0.072 s
OK
2.
0.072 s
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3.
0.072 s
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4.
0.072 s
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5.
0.072 s
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6.
0.072 s
OK
1.
0.072 s
OK
2.
0.072 s
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3.
0.072 s
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4.
0.072 s
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5.
0.072 s
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6.
0.072 s
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1.
0.072 s
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2.
0.072 s
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3.
0.072 s
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4.
0.072 s
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5.
0.072 s
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6.
0.072 s
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1.
0.072 s
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0.072 s
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6.
0.072 s
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1.
0.072 s
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2.
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3.
0.072 s
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4.
0.072 s
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5.
0.072 s
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6.
0.072 s
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1.
0.072 s
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2.
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3.
0.072 s
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4.
0.072 s
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5.
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6.
0.072 s
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2.
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3.
0.072 s
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4.
0.072 s
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5.
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6.
0.072 s
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expand all
Performance tests
1.
0.116 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.156 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.208 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.208 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.156 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK
1.
0.120 s
OK
2.
0.072 s
OK
3.
0.072 s
OK
4.
0.072 s
OK
5.
0.072 s
OK
6.
0.072 s
OK