A+B Again

A + B Again
Time Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 19603 Accepted Submission(s): 8448

Problem Description

There must be many A + B problems in our HDOJ , now a new one is coming.
Give you two hexadecimal integers , your task is to calculate the sum of them,and print it in hexadecimal too.
Easy ? AC it !

Input

The input contains several test cases, please process to the end of the file.
Each case consists of two hexadecimal integers A and B in a line seperated by a blank.
The length of A and B is less than 15.

Output

For each test case,print the sum of A and B in hexadecimal in one line.

Sample Input

+A -A
+1A 12
1A -9
-1A -12
1A -AA

Sample Output

0
2C
11
-2C
-90

题目给定条件：The length of A and B is less than 15. 也就说两个十六进制数转换为二进制，最多只有 15*4=60位 预算结果转换为二进制，最多只有 61 位，那么就只能用64，__int 64参看下面链接：

http://blog.youkuaiyun.com/yang_chengfeng/article/details/49835285

#include<stdio.h>
int main()
{
     __int64 a,b;
     for (;scanf("%I64x%I64x",&a,&b)!=EOF;){
          printf(a+b<0?"-%I64X\n":"%I64X\n",a+b<0?-a-b:a+b);
     }
     return 0;
}

对于C++,大家可以看看：http://blog.youkuaiyun.com/xujinsmile/article/details/7836413很详细