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).
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.
-1000000 9
Sample Output:
-999,991
一刷：（c语言）
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
void print(int len ,int p[])
{
int i = 0;
if (len%3!=0)
{
for (; i < len % 3; i++)
{
printf("%d", p[i]);
}
printf(",");
}
int count = 0;
for (; i < len; i++)
{
printf("%d", p[i]);
count++;
if (count % 3 == 0 && i < len - 1)
{
printf(",");
}
}
}
int main()
{
int a=0, b=0;
if(scanf("%d %d", &a, &b)==1);
while (a < -1000000 || b>1000000)
{
if(scanf("%d %d", &a, &b)==1);
}
int isNegative = 0;
int sum = a + b;
if (sum<0)
{
isNegative = 1;
sum = -sum;
}
int len = 0;
int k = sum;
while (k > 0)
{
k /= 10;
len++;
}
int *p = (int *)malloc(sizeof(int)*len);
int mask = (int)pow(10, len - 1);//分解
if (len < 4)
{
if (isNegative==1)
{
printf("%d", -sum);
}
else
{
printf("%d", sum);
}
}
else
{
for (int i = 0; i < len; i++)
{
p[i] = sum / mask;
sum %= mask;
mask /= 10;
}
if (isNegative == 1)
{
printf("-");
print(len, p);
}
else
{
print(len, p);
}
}
return 0;
}
二刷：（c++）
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
vector<int> v;
int main()
{
//freopen("in.txt", "r", stdin);
int a, b, sum;
cin >> a >> b;
sum = a + b;
if (sum<0)
{
cout << "-";
sum = -sum;
}
if (sum==0)
{
cout << 0 << endl;
return 0;
}
while (sum!=0)
{
v.push_back(sum % 10);
sum /= 10;
}
reverse(v.begin(), v.end());//翻转数组
for (int i = 0; i < v.size(); i++)
{
cout << v[i];
if (v.size()>3)//只有长度大于3才需要输出逗号
{
if ((i + 1) % 3 == v.size() % 3&&((i+1)!=v.size()))
{
cout << ",";
}
}
}
cout << endl;
return 0;
}
吾：java做法：（“，”逗号是分组的分隔符）见java核心（卷1）p58！c++好像不行
import java.io.Console;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
int a,b;
Scanner in=new Scanner(System.in);
a=in.nextInt();
b=in.nextInt();
int sum=a+b;
System.out.printf("%,d", sum);
}
}
柳：妙啊
#include <iostream>
#include <string>
using namespace std;
int main()
{
//freopen("in.txt", "r", stdin);
int a, b;
cin >> a >> b;
string s = to_string(a + b);
for (int i = 0; i < s.length(); i++)
{
cout << s[i];
if (s[i]=='-')
{
continue;
}
if ((i+1)%3==s.length()%3&&(i!=s.length()-1))
{
cout << ",";
}
}
return 0;
}
