准备每天刷两题PAT真题
1001 A+B Format
模拟输出，注意格式
1 #include <cstdio> 2 #include <cstring> 3 #include <iostream> 4 #include <algorithm> 5 using namespace std; 6 7 string ans = ""; 8 9 int main() { 10 int a, b, c, cnt = 0; 11 cin >> a >> b; 12 c = a + b; 13 if(c == 0) { 14 cout << 0 << endl; 15 return 0; 16 } 17 while(c) { 18 if(cnt % 3 == 0 && cnt != 0) ans = ans + ","; 19 char ch = abs(c % 10) + '0'; 20 ans = ans + ch; 21 c /= 10; 22 cnt++; 23 } 24 reverse(ans.begin(), ans.end()); 25 if(a + b < 0) ans = "-" + ans ; 26 cout << ans << endl; 27 return 0; 28 }