题目链接:https://ac.nowcoder.com/acm/contest/3003/J
题目大意:
思路:
#include<bits/stdc++.h>
#define LL long long
#define mid (l+r)/2
using namespace std;
const LL mod = 1e9+7;
struct Node{
int l, r;
LL ks, bs;
}node[5000000];
LL b[200005], k[200005];
void BT(int i, int l, int r){
node[i].l=l; node[i].r=r;
if(l==r){
node[i].ks=k[l]; node[i].bs=b[l];
return ;
}
BT(i<<1, l, mid); BT((i<<1)+1, mid+1, r);
node[i].ks=node[i<<1].ks*node[(i<<1)+1].ks%mod;
node[i].bs=(node[i<<1].bs*node[(i<<1)+1].ks%mod+node[(i<<1)+1].bs)%mod;
}
void gx(int i, int x, LL k, LL b){
if(node[i].l==node[i].r){
node[i].ks=k; node[i].bs=b;
return ;
}
if(x<=(node[i].l+node[i].r)/2){
gx(i<<1, x, k, b);
}
else{
gx((i<<1)+1, x, k, b);
}
node[i].ks=node[i<<1].ks*node[(i<<1)+1].ks%mod;
node[i].bs=(node[i<<1].bs*node[(i<<1)+1].ks%mod+node[(i<<1)+1].bs)%mod;
//cout<<node[i].l<<" "<<node[i].r<<" "<<node[i].ks<<" "<<node[i].bs<<endl;
}
LL ansk=1, ansb=0;
void cx(int i, int l, int r){
if(node[i].l==l&&node[i].r==r){
ansk=ansk*node[i].ks%mod;
ansb=(ansb*node[i].ks%mod+node[i].bs)%mod;
return ;
}
if(r<=(node[i].l+node[i].r)/2) cx(i<<1, l, r);
else if(l>(node[i].l+node[i].r)/2) cx((i<<1)+1, l, r);
else cx(i<<1, l, (node[i].l+node[i].r)/2), cx((i<<1)+1, (node[i].l+node[i].r)/2+1, r);
}
int main(){
int n, m;
scanf("%d%d", &n, &m);
for(int i=1; i<=n; i++){
scanf("%lld", &k[i]);
}
for(int i=1; i<=n; i++){
scanf("%lld", &b[i]);
}
BT(1, 1, n);
while(m--){
int op;
scanf("%d", &op);
if(op==1){
int x, y, z;
scanf("%d%d%d", &x, &y, &z);
gx(1, x, y, z);
}
else{
int x, y;
scanf("%d%d", &x, &y);
ansk=1; ansb=0;
cx(1, x, y);
printf("%lld\n", (ansk+ansb)%mod);
}
}
return 0;
}