短的题解（二进制）

#include <bits/stdc++.h>
using namespace std;
using LL = long long;
LL l, r, cnt;
bool ismhs(LL x) {
    if(x <= 1) return false;
    LL ocnt = 0;
    while(x) {
        ocnt += x & 1;
        x >>= 1;
    }
    return ocnt <= 2;
}
int main() {
    scanf("%lld%lld", &l, &r);
    for(LL i = l; i <= r; i ++) if(ismhs(i)) cnt ++;
    printf("%lld\n", cnt);
    return 0;
}