class Solution {
public:
int giveGem(vector<int>& gem, vector<vector<int>>& operations) {
int n = operations.size();
for (int i = 0; i < n; i ++ ) {
int l = operations[i][0], r = operations[i][1];
int t = gem[l] / 2;
gem[l] -= t, gem[r] += t;
}
int maxv = 0, minv = 1e9;
for (auto c: gem) {
maxv = max(maxv, c);
minv = min(minv, c);
}
return maxv - minv;
}
};