Submission #1213473

#	Time	Username	Problem	Language	Result	Execution time	Memory
1213473		minhpk	Palindrome-Free Numbers (BOI13_numbers)	C++20	100 / 100	1 ms	328 KiB

numbers

#include <bits/stdc++.h>
#define int long long
using namespace std;
int a,b;
string s;
int f[20][2][11][11][2];

int dp(int i,int idx,int j,int k,int keep){
    if (i>=s.size()){
        return keep;
    }
    if (f[i][idx][j][k][keep]!=-1){
        return f[i][idx][j][k][keep];
    }
    f[i][idx][j][k][keep]=0;
    int max1;
    if (idx){
        max1=s[i]-'0';
    }else{
        max1=9;
    }
    int ans=0;
    for (int t=0;t<=max1;t++){
         if (t==0){
             if (k==10){
                 ans+= dp(i+1,0,10,10,0);
             }else{
                 int pre=0;
                 if ((t==k)||(t==j)){
                     pre=1;
                 }
                 ans+= dp(i+1,(t==max1)&&(idx),k,t,max(keep,pre));
             }
         }else{
             int pre=0;
             if ((t==k)||(t==j)){
                     pre=1;
             }
             ans+= dp(i+1,(t==max1)&&(idx),k,t,max(keep,pre));
         }
    }
    return f[i][idx][j][k][keep]=ans;
}

int get(int n){
   if (n==-1){
      return 0;
   }
   s=to_string(n);
   s='#'+s;
   memset(f,-1,sizeof f);
   return dp(1,1,10,10,0);
}

signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> a >> b;
    a--;
    cout << (b-a)-(get(b)-get(a)) << "\n";
    return 0;
}

• Subtask 1: 25 / 25
• Subtask 2: 75 / 75