2sum.py

import time

f = open('./integers/1000.txt', 'r')
x = map(int, f.read().splitlines())

def solution(nums):
    n = len(nums)
    res = 0
    for i in range(n):
        for j in range(i + 1, n):
            if nums[i] + nums[j] == 0:
                res += 1
    return res

start = time.time()
result = solution(x)
time = (time.time() - start);

# 1k | 253 | 0.049782037735
# 2k | 969 | 0.189519166946
# 4k | 4007 | 0.749423980713
# 8k | 16204 | 3.02656292915
# 16k | 63842 | 12.532490015
# 32k | 256505 | 50.928894043
# 64k | ~256505*4 | ~203