【luogu3353】在你窗外閃耀的星星 前綴和

坑點就是一個點上會有很多星星qwq

#include<iostream>
#include<cstdio>
#include<cctype>
using namespace std;
int s[1010000],n,m,ToT,ans;
inline int read() {
    int ret=0;int ch=getchar();
    for (;!isdigit(ch);ch=getchar());
    for (;isdigit(ch);ch=getchar()) ret=ret*10+ch-'0';
    return ret;

}
int main() {
    n=read();m=read();
    for (int i=1;i<=n;i++) {
        int x=read(),y=read();
        s[x]+=y;ToT=max(ToT,x);
    }
    for (int i=1;i<=ToT;i++) s[i]+=s[i-1];
    for (int i=ToT;i-m>=0;i--) ans=max(s[i]-s[i-m],ans); 
    printf("%d\n",ans);
    return 0;
}