In this problem, we are given $n$ lines ($1 \leq n \leq 100$) of
three integers $-100 \leq x_i, y_i, z_i \leq 100$ for each $i = 1, 2,
\dots, n$. Print YES if and only if \[ \sum_{i=1}^n x_i =
\sum_{i=1}^n y_i = \sum_{i=1}^n z_i = 0 \] Otherwise print
NO.
Problems like this are all about how quickly you can write a solution for them. Generally, the fewer lines of code you need to get accepted, the better.