题解 | #二叉树#

#include <iostream>
#include <cstdio>

using namespace std;

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

int main() {
    long long m,n;
    while(scanf("%ld%ld",&m,&n)!=EOF){
        printf("%ld",Sum(m,n));
    }
    return 0;
}