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:
def 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 Python
Time spent on task 20 minutes
Notes
not defined yet
Code: 01:34:59 UTC,
java,
autosave
Code: 01:38:00 UTC,
py,
autosave
Code: 01:39:57 UTC,
py,
verify,
result: Failed
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[1, 2, 5, 8, 10, 20]
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[1, 5, 10, 50]
Code: 01:41:06 UTC,
py,
verify,
result: Failed
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[20, 10, 8, 5, 2, 1]
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[50, 10, 5, 1]
Code: 01:41:50 UTC,
py,
verify,
result: Failed
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[20, 10, 8, 5, 2, 1] 0 20 1 10 2 8 3 5 4 2 5 1
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[50, 10, 5, 1] 0 50 1 10 2 5 3 1
Code: 01:42:28 UTC,
py,
verify,
result: Failed
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.040 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
6 [20, 10, 8, 5, 2, 1] 0 20 1 10 2 8 3 5 4 2 5 1
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.040 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
4 [50, 10, 5, 1] 0 50 1 10 2 5 3 1
Code: 01:42:38 UTC,
py,
autosave
Code: 01:43:15 UTC,
py,
autosave
Code: 01:45:28 UTC,
py,
autosave
Code: 01:45:58 UTC,
py,
autosave
Code: 01:48:29 UTC,
py,
autosave
Code: 01:48:59 UTC,
py,
autosave
Code: 01:49:29 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
while now_num + 2 > length_A-1:
print(sorted_A[now_num], sorted_A[now_num], sorted_A[now_num])
now_num += 1
Code: 01:49:37 UTC,
py,
verify,
result: Failed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
while now_num + 2 > length_A-1:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.
Code: 01:49:50 UTC,
py,
verify,
result: Failed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
while now_num + 2 > length_A-1:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.
Code: 01:50:09 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
while now_num + 2 length_A-1:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Code: 01:50:11 UTC,
py,
verify,
result: Failed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
while now_num + 2 < length_A-1:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
20 10 8 10 8 5 8 5 2
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
50 10 5
Code: 01:50:23 UTC,
py,
verify,
result: Failed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A-1:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[20, 10, 8, 5, 2, 1] 20 10 8 10 8 5 8 5 2
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[50, 10, 5, 1] 50 10 5
Code: 01:50:34 UTC,
py,
verify,
result: Failed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Analysis
expand all
Example tests
example
example, positive answer, length=6
example, positive answer, length=6
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[20, 10, 8, 5, 2, 1] 20 10 8 10 8 5 8 5 2 5 2 1
example1
example, answer is zero, length=4
example, answer is zero, length=4
✘
RUNTIME ERROR
tested program terminated with exit code 1
tested program terminated with exit code 1
1.
0.036 s
RUNTIME ERROR,
tested program terminated with exit code 1
stderr:
Invalid result type, int expected, <class 'NoneType'> found.stdout:
[50, 10, 5, 1] 50 10 5 10 5 1
Code: 01:50:59 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
now_num += 1
Code: 01:51:15 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if s
now_num += 1
Code: 01:51:41 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num]
now_num += 1
Code: 01:51:53 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num]
now_num += 1
return 0
Code: 01:52:12 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num]
now_num += 1
return 0
Code: 01:52:42 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2]
now_num += 1
return 0
Code: 01:53:03 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and
sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and
sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2]
now_num += 1
return 0
Code: 01:53:17 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and
sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and
sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]
now_num += 1
return 0
Code: 01:53:27 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and
sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and
sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
now_num += 1
return 0
Code: 01:53:38 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
now_num += 1
return 0
Code: 01:53:52 UTC,
py,
verify,
result: Passed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
return 1
now_num += 1
return 0
User test case 1:
[50, 10, 5]
Analysis
expand all
Example tests
1.
0.036 s
OK
stdout:
[20, 10, 8, 5, 2, 1] 20 10 8 10 8 5
1.
0.036 s
OK
stdout:
[50, 10, 5, 1] 50 10 5 10 5 1
expand all
User tests
1.
0.036 s
OK
function result: 0
function result: 0
stdout:
[50, 10, 5] 50 10 5
Code: 01:54:06 UTC,
py,
autosave
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
#print(sorted_A)
while now_num + 2 < length_A:
print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
return 1
now_num += 1
return 0
Code: 01:54:13 UTC,
py,
verify,
result: Passed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
#print(sorted_A)
while now_num + 2 < length_A:
#print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
return 1
now_num += 1
return 0
User test case 1:
[50, 10, 5]
Analysis
Code: 01:54:18 UTC,
py,
verify,
result: Passed
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
#print(sorted_A)
while now_num + 2 < length_A:
#print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
return 1
now_num += 1
return 0
User test case 1:
[50, 10, 5]
Analysis
Code: 01:54:21 UTC,
py,
final,
score: 
100
# you can write to stdout for debugging purposes, e.g.
# print("this is a debug message")
def solution(A):
length_A = len(A)
sorted_A = sorted(A, reverse=True)
now_num = 0
#print(sorted_A)
while now_num + 2 < length_A:
#print(sorted_A[now_num], sorted_A[now_num+1], sorted_A[now_num+2])
if sorted_A[now_num] + sorted_A[now_num + 1] > sorted_A[now_num+ + 2] and sorted_A[now_num + 1] + sorted_A[now_num + 2] > sorted_A[now_num] and sorted_A[now_num] + sorted_A[now_num + 2] > sorted_A[now_num+ + 1]:
return 1
now_num += 1
return 0
Analysis summary
The solution obtained perfect score.
Analysis
Detected time complexity:
O(N*log(N))
expand all
Correctness tests
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.036 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
expand all
Performance tests
1.
0.048 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.088 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.168 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.212 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.176 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK
1.
0.152 s
OK
2.
0.036 s
OK
3.
0.036 s
OK
4.
0.036 s
OK
5.
0.036 s
OK
6.
0.036 s
OK