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Once upon a time, in a small village in the snowy mountains, there lived a young man named Sorabh. Sorabh loved playing with snowballs, and he had a collection of snowballs of different weights. One day, while he was playing with snowballs, he thought of a game that he could play with them. He called it Smash the Snowballs.

The rules of the game were simple. On each turn, Sorabh would choose the two heaviest snowballs and smash them together. If the two snowballs had the same weight, they would both be destroyed. If they had different weights, the lighter snowball would be destroyed, and the heavier snowball's weight would be reduced by the weight of the lighter snowball. Sorabh continued playing the game until there was only one snowball left.

Can you help Sorabh determine the weight of the last remaining snowball? If all the snowballs get destroyed and there remains no snowballs at the end, then assume the weight of the last remaining snowball as $0$.

The weights of all the snowballs are as follows: $[4, 3, 11, 8, 2, 5, 13, 7]$