Gao The Sequence

Gao The Sequence

 计算出一个差值数组C[i], 一种操作， 找一个delate有C[i]-=delaie，找任意多个C[j]-=D[j] (j<i) 使sum(D[j])=delate, 问能否使C[i]全部赋0.

#include<cstdio>
#define ll long long
int main(){
    int n;
    while(~scanf("%d",&n)){
        ll a,b,c,s=0,m=0;
        while(n--){
            scanf("%lld%lld",&a,&b);
            c=a-b;s+=c;
            if(c>m)m=c;
        }
        puts(s&1||s<m<<1?"NO":"YES");
    }
    return 0;
}