Backpacking

import sys
 
s = 0
 
for line in sys.stdin:
    line = line.strip()
    data = line.split()
    if len(data) == 2:
        a, b = data
        s += int(a) + int(b)
 
print(s)
    

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED