同济大学C++题目

#include <iostream>
#define N 100
using namespace std;
int main()
{
	char s[N];
	int i,sn, sum=0;  //程序目的：从字符数组里提取数字并加和
	cin>>s;
	while (strcmp(s, "end") != 0)
	{
		__(1)__;
		char* p = s;
		for (i = 0; __(2)__; i++)
			sn = sn * 10 + __(3)__;
		sum = sum + sn;
		__(4)__;
	}
	cout << sum << endl;
	system("pause");
	return 0;
}

程序填空题，令人疑惑

题目给出的示例：

这么简单的题都能做错，我看我是完全不懂哦

标答如下：

#include<iostream>
using namespace std;
int main()
{
    char s[N];
    int i, sn, sum = 0;//sn存放数字字符串s转换成的整数
    cout << "please enter numbers to sum:" << endl;
    cin >> s;
    while (strcmp(s, "end") != 0)
    {
        sn=0;
        for (i = 0; s[i]!='\0'; i++)//该循环将数字字符串s转换成相应的整数
            sn = sn * 10 +s[i] - '0';
        sum = sum + sn;
        cin>>s;
    }
    cout << "sum=" << sum << endl;
    system("pause");
    return 0;
}