#include <bits/stdc++.h> using namespace std; #define USE_STD_IO 1 #if USE_STD_IO #define fin cin #define fout cout #else ifstream fin(".in"); ofstream fout(".out"); #endif struct Tablou { long long mar, val; } v[500002]; long long n, i, val, ma, rasp; static inline bool Cmp(Tablou t1, Tablou t2) { return t1.mar < t2.mar; } int main() { if(USE_STD_IO) ios_base::sync_with_stdio(false); fin.tie(NULL); fout.tie(NULL); fin >> n; for(i = 1; i <= n; i++) { fin >> v[i].mar >> v[i].val; } sort(v + 1, v + n + 1, Cmp); for(i = 1; i <= n; i++) { ma = max(ma, v[i].mar - val); val += v[i].val; rasp = max(rasp, ma + val - v[i].mar); } fout << rasp; return 0; }