PTA 1001 A+B Format

问题描述：

Calculate a+b and output the sum in standard format -- that is, the digits must be separated into groups of three by commas (unless there are less than four digits).

Input Specification:

Each input file contains one test case. Each case contains a pair of integers a and b where −. The numbers are separated by a space.

Output Specification:

For each test case, you should output the sum of a and b in one line. The sum must be written in the standard format.

Sample Input:

-1000000 9

 

Sample Output:

-999,991

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没啥难的，水一篇罢了，帮狗子同学改的代码，缩进没改。

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代码：

 #include <iostream>
 #include <cmath>
 using namespace std;
 int main()
 {
  int a,b,sum=;
  long x;
  char num[]={};
  cin>>a>>b;
  x=a+b;
  if (x>){
  while (x!=)
  {
   num[sum]=x%+;
   x=x/;
   sum++;
  }
  for (int i=sum-;i>=;i--)
  {
   cout<<num[i];
   if (i%==&&i!=)
    cout<<",";
  }}
  else if (x==)
   cout<<"";
  else
  {
   while (x!=)
  {
   num[sum]=abs(x%)+;
   x=x/;
   sum++;
  }
  cout<<"-";
  for (int i=sum-;i>=;i--)
  {
   cout<<num[i];
   if (i%==&&i!=)
    cout<<",";
  }}
  return ;
 }