[백준] 2455번 : 지능형 기차 - C++

https://www.acmicpc.net/problem/2455

#include <iostream>

using namespace std;

int main() {
    int a,b;
    int sum=0;
    int max=0;
    for(int i=0;i<4;i++){
        cin>>a>>b;
        sum+=-a+b;
        if(sum>=max) max=sum;
    }
    cout<<max;
}