Submission

Score: 20

User: patsa_v

Problemset: Strobogrammatic Numbers

Language: cpp

Time: 0.004 second

Submitted On: 2026-10-14 14:11:12

#include <bits/stdc++.h>
using namespace std;

#define ll long long
int len,n,cnt = 0;
int arr[5] ={0,1,6,8,9};
int rot[10] = {0,1,-1,-1,-1,-1,9,-1,8,6};
int d[16];
ll l,r;

void stro(int pos){
    if(pos == n) {
        for(int j=0;j<len/2;j++){
            d[len-j-1] = rot[d[j]];
        }
        ll v = 0;
        for(int j=0;j<len;j++){
            v = v*10+d[j];
        }
        if(v >= l && v<= r)cnt ++;
        return;
    }
    for(int j=0;j<5;j++){
        int x = arr[j];
        if(x == 0 && pos == 0 && len > 1)continue;
        if(len%2 == 1 && pos == n-1 && rot[x] != x) continue;
        d[pos] = x;
        stro(pos+1);
    }
}

int main(){
    cin >> l >> r;
    for(len = 1;len<=3;len++){
        n = (len+1)/2;
        stro(0);
    }
    cout << cnt;
    return 0;
}