1001. A+B Format(20分)
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 −106≤a,b≤106. 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 结尾无空行
Sample Output:
-999,991 结尾无空行
#include <iostream>
using namespace std;
int main()
{
int a, b;
cin >> a >> b;
string s = to_string(a + b);
int len = s.length();
for (int i = 0; i < len; i++)
{
cout << s[i];
if (s[i] == '-')
{
continue;
}
if ((len - 1 - i) % 3 == 0 && i != len - 1)
cout << ",";
}
return 0;
}
我要麻了,第一题还出错,写了半小时。开始想复杂了,用了栈和整数求余。其实很简单,要注意的点就是算逗号的时候需要倒置求余。