题解 | #二叉树#

#include <iostream>
#include <cstdio>

using namespace std;

int binary_tree(int m, int n){
    if (m > n){
        return 0;
    }else{
        return binary_tree(2 * m, n) + binary_tree(2 * m + 1, n) + 1;
    }
}

int main(){
    int m, n;
    while (scanf("%d%d", &m, &n) != EOF)
    {
        if(m==0 && n==0){
            break;
        }
        printf("%d", binary_tree(m, n));
    }
    
    return 0;
}