分块！！求调！悬赏一个关注！

#include<bits/stdc++.h>
#define itn int
#define ll long long
#define ull unsigned long long
using namespace std;
const int N=1e5+10;
int n,m;
int block[N];
int len;
int a[N];
int sig[N];//sig[i]代表第i个块的正负性 
int quer(int l,int r){
	int x=1;
	for(itn i=l;i<=min(block[l]*len,r);i++){
		x*=a[i];
	}if(block[l]==block[r]) return x;
	for(itn i=(block[r]-1)*len+1;i<=r;i++){
		x*=a[i];
	}if( (block[r]-block[l])==1) return x;
	for(int i=block[l]+1;i<=block[r]-1;i++){
		x*=sig[i];
	}
	return x;
}
int updata(int x,itn y){
	a[x]=y;
	int tmp=1;
	for(itn i=(block[x]-1)*len+1;i<=min(n,block[x]*len);i++){
		tmp*=a[i];
	}
	return tmp;
}
int main(){
//	freopen("inter1.in","r",stdin);
//	freopen("inter.out","w",stdout);
	while(cin>>n>>m){
		memset(block,0,sizeof block);
		memset(a,0,sizeof a);memset(sig,0,sizeof sig);
		len=sqrt(n);
		for(itn i=1;i<=n;i++){
			scanf("%d",&a[i]);
			if(a[i]>0) a[i]=1;//怕爆int，缩小范围 
			if(a[i]<0) a[i]=-1;
			block[i]=(i-1)/len+1;
		}
		for(int t=1;t<=block[n];t++){//更新每个块的正负性 
			int x=1;
			for(int i=(t-1)*len+1;i<=min(n,len*t);i++){
				x*=a[i];
			}
			if(x<0){
				sig[t]=-1;
			}if(x>0){
				sig[t]=1;
			}if(x==0){
				sig[t]=0;
			}
		}
		for(int t=1;t<=m;t++){
			char c[5];
			int x,y;
			scanf("%s%d%d",&c,&x,&y);
			if(y>0) y=1;
			if(y<0) y=-1;
			if(c[0]=='C'){
				int tmp=updata(x,y);
				if(tmp<0){
					sig[block[x]]=-1;
				}if(tmp>0){
					sig[block[x]]=1;
				}if(tmp==0){
					sig[block[x]]=0;
				}
			}
			if(c[0]=='P'){
				int tmp=quer(x,y);
				if(tmp>0){
					printf("+");
				}if(tmp<0){
					printf("-");
				}if(tmp==0){
					printf("0");
				}
			}
		}
		cout<<"\n";
	}
    return 0;
}