A. Bits
Time Limit: 20 Sec
Memory Limit: 256 MB
题目连接
http://codeforces.com/contest/484/problem/A
Description
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.
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 children in the line (1 ≤ n ≤ 106).
The second line contains n integers ai — the charisma of the i-th child ( - 109 ≤ ai ≤ 109).
Output
For each query print the answer in a separate line.
Sample Input
3
1 2
2 4
1 10
Sample Output
1
3
7
HINT
题意
给你q次询问,每次询问,问你l<=x<=y中,x的2进制中,1的个数最多的那个数是什么
题解:
贪心,从x开始,依次从最小位开始,把x中的0变成1,直到大于y
然后输出答案就好了
代码
#include<iostream> #include<stdio.h> #include<math.h> using namespace std; int main() { int n;scanf("%d",&n); while(n--) { long long x,y;scanf("%lld%lld",&x,&y); long long i; long long ans=x; for(i=x;i<=y;i+=~i&-~i)ans=i; printf("%lld ",ans); } }