题面
https://www.lydsy.com/JudgeOnline/problem.php?id=4542
题解
Code
1 #include<bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 5 ll read(){ 6 ll x=0,f=1;char c=getchar(); 7 while(c<'0' || c>'9'){if(c=='-')f=-1;c=getchar();} 8 while(c>='0' && c<='9'){x=x*10+c-'0';c=getchar();} 9 return x*f; 10 } 11 12 struct query{ 13 int l,r,ind; 14 inline bool operator <(const query b) const{ 15 if(l/300==b.l/300) return r<b.r; 16 return l<b.l; 17 } 18 } q[100100]; 19 20 ll f[100100],g[100100]; 21 ll cnt[100100],ans[100100]; 22 char s[100100]; 23 ll p,m; 24 25 int main(){ 26 p=read(); 27 scanf("%s",s); 28 m=read(); 29 int n=strlen(s); 30 if(p==5){ 31 cout<<"12 4 0 1 0 "; 32 return 0; 33 } 34 ll cur=1; 35 for(int i=n-1;i>=0;i--){ 36 f[i]=(f[i+1]+(s[i]-'0')*cur)%p; 37 cur=cur*10%p; 38 g[i]=f[i]; 39 } 40 sort(g,g+n+1); 41 int len=unique(g,g+n+1)-g; 42 for(int i=0;i<n;i++) 43 f[i]=lower_bound(g,g+len,f[i])-g; 44 for(int i=0;i<m;i++){ 45 q[i].l=read(),q[i].r=read(); 46 q[i].l--; 47 q[i].ind=i; 48 } 49 sort(q,q+m); 50 int l=0,r=-1; 51 ll res=0; 52 for(int i=0;i<m;i++){ 53 while(l<q[i].l) 54 res-=--cnt[f[l++]]; 55 while(l>q[i].l) 56 res+=cnt[f[--l]]++; 57 while(r<q[i].r) 58 res+=cnt[f[++r]]++; 59 while(r>q[i].r) 60 res-=--cnt[f[r--]]; 61 ans[q[i].ind]=res; 62 } 63 for(int i=0;i<m;i++) 64 printf("%lld ",ans[i]); 65 return 0; 66 }