문제
풀이
#include <iostream>
using namespace std;
void solve(void) {
int n; cin >> n;
int ans = 1;
while (n--) {
int a, b; cin >> a >> b;
ans += b + (b < 0) - a - (a < 0);
}
cout << ans - (ans <= 0);
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}