Find all triplets whose sum is equal to given number.

threeNumberSum.py

#   ////////////////////////////////////////////////
#  --------------Three Number Sum-----------------
# ///////////////////////////////////////////////



# time complexity O(n^2)
# space complexity O(n)

def tripletSum(arr, v):
    l_n = len(arr)
    result = []
    for i in range(l_n):                                        # runs n times
        for j in range(i+1,l_n):                                # runs n-1 times
            for k in range(j+1,l_n):                            # runs n-2 times
                if arr[i] + arr[j] + arr[k] == v:
                    result.append([arr[i] , arr[j] , arr[k]])
    return result

print(tripletSum([1,2,3,4,5,6,-1],6))


# time complexity O(n^2)
# space complexity O(n)

def tripletSum1(arr,v):
    l_n = len(arr)
    result = []
    arr.sort()
    for i in range(l_n):                                       # runs n times
        r = i+1
        l = l_n-1
        while l>r:                                             # runs n-1 times
            s_m = arr[i] + arr[r] + arr[l]
            if s_m == v:
                result.append([arr[i] , arr[l] , arr[r]])
                r += 1
                l -= 1
            elif s_m < v:
                r +=1
            else:
                l -= 1
    return result

print(tripletSum([1,2,3,4,5,6,-1],6))