*Given an array of distinct integers. The task is to count all the triplets such that sum of two elements equals the third element.*

**Input:**The first line of input contains the number of test cases. Each test case consists of two lines.

*First line of contains size of array*

T

*he second line contains N space separated elements.*

**Output:**For each test case, print the count of all triplets, in new line Else print “-1”.GeeksForGeeks link: Link

*SOLUTION **BODY*

*SOLUTION*

*BODY*

```
def solution(array):
triplets = 0
range_len = len(array)
for i in range(range_len):
temp_arr = array[i+1::]
val = set(array)
for j in temp_arr:
value = array[i] + j
if value in val:
triplets = triplets + 1
else:
pass
if triplets == 0:
return -1
else:
return triplets
```

**Things added:** To check if triplet exists, I have used sets{} as it has O(1) lookup time..**Execution Time: **0.71

```
def inputList(n):
while True:
print(f"Enter space separated elements of size {n}")
array = [int(num) for num in input().split()]
if len(array) == n:
break
else:
print("Entered value doesn't match with size N provided")
array.sort()
return array
```

*MAIN BODY*

*MAIN BODY*

```
def main():
while True:
try:
T = int(input("Enter integer T denoting the number of test cases: "))
array = {}
for num in range(T):
N = int(input("Enter integer N denoting size of array: "))
array[num+1] = inputList(N)
print("")
triplet = solution(array[num+1])
print(f"Number of triplets in {array[num+1]} is {triplet}n")
break
except Exception as e:
print(e)
```

```
main()
```

```
Enter integer T denoting the number of test cases: 2
Enter integer N denoting size of array: 4
Enter space separated elements of size 4
1 5 3 2
Number of triplets in [1, 2, 3, 5] is 2
Enter integer N denoting size of array: 3
Enter space separated elements of size 3
3 2 7
Number of triplets in [2, 3, 7] is -1
```