提交情况

#include <bits/stdc++.h>
using namespace std;
#define N 50005
inline int read(){
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-') f=-1; ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-48; ch=getchar();}
    return x*f;
}
int n,q;
int a[N];
int main(){
	n=read();
	for(int i=1;i<=n;i++) a[i]=read();
	q=read();
	int op,x,y;
	while(q--){
		op=read(); x=read(); y=read();
		if(op==0){
			a[x]=y;
		}
		else{
			int sum=0,ans=0,maxn=-1e9;
			for(int i=x;i<=y;i++){
				maxn=max(maxn,a[i]);
				if(sum<0) sum=0;
				sum+=a[i];
				ans=max(ans,sum);
			}
			if(maxn<=0) printf("%d\n",maxn);
			else printf("%d\n",ans);
		}
	}
	return 0;
}