Tasks Details
easy
1.
Triangle
Determine whether a triangle can be built from a given set of edges.
Task Score
93%
Correctness
90%
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:
class Solution { public int solution(int[] 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 C#
Time spent on task 26 minutes
Notes
not defined yet
Code: 09:18:16 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < A.Length; i++)
{
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2])
{
return 1;
}
}
return 0;
}
}
Analysis
expand all
Example tests
1.
0.038 s
OK
1.
0.037 s
RUNTIME ERROR,
tested program terminated unexpectedly
stderr:
Unhandled Exception: System.IndexOutOfRangeException: Array index is out of range. at Solution.solution (System.Int32[] A) [0x00000] in <filename unknown>:0 at SolutionWrapper.run (System.String input, System.String output) [0x00000] in <filename unknown>:0 at SolutionWrapper.Main (System.String[] args) [0x00000] in <filename unknown>:0 [ERROR] FATAL UNHANDLED EXCEPTION: System.IndexOutOfRangeException: Array index is out of range. at Solution.solution (System.Int32[] A) [0x00000] in <filename unknown>:0 at SolutionWrapper.run (System.String input, System.String output) [0x00000] in <filename unknown>:0 at SolutionWrapper.Main (System.String[] args) [0x00000] in <filename unknown>:0
Code: 09:19:45 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < A.Length; i++)
{
if(A[i + 2] == null) return 0;
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2])
{
return 1;
}
}
return 0;
}
}
Analysis
expand all
Example tests
1.
0.039 s
OK
1.
0.035 s
RUNTIME ERROR,
tested program terminated unexpectedly
stderr:
Unhandled Exception: System.IndexOutOfRangeException: Array index is out of range. at Solution.solution (System.Int32[] A) [0x00000] in <filename unknown>:0 at SolutionWrapper.run (System.String input, System.String output) [0x00000] in <filename unknown>:0 at SolutionWrapper.Main (System.String[] args) [0x00000] in <filename unknown>:0 [ERROR] FATAL UNHANDLED EXCEPTION: System.IndexOutOfRangeException: Array index is out of range. at Solution.solution (System.Int32[] A) [0x00000] in <filename unknown>:0 at SolutionWrapper.run (System.String input, System.String output) [0x00000] in <filename unknown>:0 at SolutionWrapper.Main (System.String[] args) [0x00000] in <filename unknown>:0
Code: 09:21:11 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < A.Length; i++)
{
if(0 < A[i + 2]) break;
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2])
{
return 1;
}
}
return 0;
}
}
Analysis
Code: 09:22:23 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < A.Length; i++)
{
if((i + 2) < A.Length) break;
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2]
&& (A[i] + A[i + 1]) > A[i + 2])
{
return 1;
}
}
return 0;
}
}
Analysis
Code: 09:23:33 UTC,
cs,
verify,
result: Failed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < A.Length; i++)
{
if((i + 2) < A.Length) break;
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i + 1] + A[i + 2]) > A[i]
&& (A[i + 2] + A[i]) > A[i + 1])
{
return 1;
}
}
return 0;
}
}
Analysis
Code: 09:24:57 UTC,
cs,
verify,
result: Passed
using System;
// you can also use other imports, for example:
// using System.Collections.Generic;
// you can write to stdout for debugging purposes, e.g.
// Console.WriteLine("this is a debug message");
class Solution {
public int solution(int[] A) {
// write your code in C# 6.0 with .NET 4.5 (Mono)
Array.Sort(A);
for(int i = 0; i < (A.Length - 2); i++)
{
// if((i + 2) < A.Length) break;
if((A[i] + A[i + 1]) > A[i + 2]
&& (A[i + 1] + A[i + 2]) > A[i]
&& (A[i + 2] + A[i]) > A[i + 1])
{
return 1;
}
}
return 0;
}
}
Analysis
Code: 09:26:47 UTC,
cs,
verify,
result: Passed
Analysis
Code: 09:26:50 UTC,
cs,
final,
score:
93
Analysis summary
The following issues have been detected: wrong answers.
Analysis
Detected time complexity:
O(N*log(N))
expand all
Correctness tests
1.
0.059 s
OK
2.
0.058 s
OK
3.
0.061 s
OK
4.
0.060 s
OK
5.
0.061 s
OK
1.
0.061 s
OK
2.
0.061 s
OK
3.
0.059 s
OK
4.
0.058 s
OK
5.
0.057 s
OK
1.
0.060 s
OK
2.
0.058 s
OK
3.
0.060 s
OK
4.
0.060 s
OK
5.
0.061 s
OK
1.
0.061 s
OK
2.
0.060 s
OK
3.
0.058 s
OK
4.
0.059 s
OK
5.
0.061 s
OK
1.
0.060 s
WRONG ANSWER,
got 0 expected 1
2.
0.058 s
OK
3.
0.059 s
OK
4.
0.058 s
OK
5.
0.058 s
OK
1.
0.058 s
OK
2.
0.061 s
OK
3.
0.061 s
OK
4.
0.061 s
OK
5.
0.061 s
OK
1.
0.061 s
OK
2.
0.061 s
OK
3.
0.061 s
OK
4.
0.060 s
OK
5.
0.061 s
OK
1.
0.059 s
OK
2.
0.061 s
OK
3.
0.060 s
OK
4.
0.061 s
OK
5.
0.061 s
OK
1.
0.060 s
OK
2.
0.060 s
OK
3.
0.058 s
OK
4.
0.059 s
OK
5.
0.058 s
OK
1.
0.061 s
OK
2.
0.060 s
OK
3.
0.061 s
OK
4.
0.061 s
OK
5.
0.060 s
OK
expand all
Performance tests
1.
0.065 s
OK
2.
0.061 s
OK
3.
0.061 s
OK
4.
0.059 s
OK
5.
0.061 s
OK
1.
0.076 s
OK
2.
0.058 s
OK
3.
0.059 s
OK
4.
0.061 s
OK
5.
0.061 s
OK
1.
0.110 s
OK
2.
0.059 s
OK
3.
0.061 s
OK
4.
0.061 s
OK
5.
0.062 s
OK
1.
0.116 s
OK
2.
0.062 s
OK
3.
0.061 s
OK
4.
0.058 s
OK
5.
0.061 s
OK
1.
0.097 s
OK
2.
0.059 s
OK
3.
0.058 s
OK
4.
0.059 s
OK
5.
0.061 s
OK
1.
0.091 s
OK
2.
0.061 s
OK
3.
0.059 s
OK
4.
0.061 s
OK
5.
0.061 s
OK