【CODEFORCES】 C. Bits

C. Bits

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

Let's denote as  the number of bits set ('1' bits) in the binary representation of the non-negative integer x.

You are given multiple queries consisting of pairs of integers l and r. For each query, find the x, such that l ≤ x ≤ r, and is maximum possible. If there are multiple such numbers find the smallest of them.

Input

The first line contains integer n — the number of queries (1 ≤ n ≤ 10000).

Each of the following n lines contain two integers l_i, r_i — the arguments for the corresponding query (0 ≤ l_i ≤ r_i ≤ 10¹⁸).

Output

For each query print the answer in a separate line.

Sample test(s)

input

3
1 2
2 4
1 10

output

1
3
7

Note

The binary representations of numbers from 1 to 10 are listed below:

1₁₀ = 1₂

2₁₀ = 10₂

3₁₀ = 11₂

4₁₀ = 100₂

5₁₀ = 101₂

6₁₀ = 110₂

7₁₀ = 111₂

8₁₀ = 1000₂

9₁₀ = 1001₂

10₁₀ = 1010₂

题解：这一题挺有意思的...因为是最小的但是1又要是最多的，所以可以想到从左端点用一个1从右往左加，直到构造出一个比r大的为止。

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

long long n,l,r;

int main()
{
    long long k,p=1;
    scanf("%I64d",&n);
    while (n--)
    {
        p=1;
        scanf("%I64d%I64d",&l,&r);
        if (l==r)
        {
            printf("%I64d\n",l);
            continue;
        }
        while (l<=r)
        {
            k=l | p;
            if (k>r) break;
            l=k;
            p<<=1;
        }
        printf("%I64d\n",l);
    }
    return 0;
}