Problem H: Eat Candy

Problem H: Eat Candy

Time Limit: 1 Sec  Memory Limit: 128 MB
Submit: 1329  Solved: 643
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Description

   There is a box with infinite volume. At first there are n candies in the box. Then every second you will eat some candies, left half of candies (round down) in the box. Then add k candies into the box. How many candies there are in the box after 109+7 seconds?

Input

   There are multiple test cases. In each test case, there are only one line contains two integers n,k(1≤n,k≤109+7)

Output

    For each test case, output the answer in one line.

Sample Input

4 52 3

Sample Output

95

HINT

In the first test case:

1st second, 4->2, 2+5 = 7

2nd second, 7->3, 3+5 = 8

3rd second, 8->4, 4+5 = 9

4th second, 9->4, 4+5 = 9

…

1000000007th            9

So there are 9 candies in the box after 1000000007 seconds.

#include<stdio.h>#include<string.h>#include<math.h>int main(){long a,b,i,re,t;while(scanf("%ld %ld",&a,&b)!=EOF){re=a/2;while(1){t=re;re+=b;re=re/2;if(t==re){printf("%ld\n",t+b);break;}}}return 0;}