#include using namespace std; #include<stdio.h> #include<string.h> using std::string; //#define MAX 1000 int substr(char dst[], char src[], int start, int len);

int main() { int start, len, sum; char src[5] = {0,0,0,0,0}; //隨意初始化，陣列大小可改，這裡是5，所以只能 輸入5個字元 char dst[5] = { 10,10,10,10,10 }; //10代表回車‘\n’ int ch; int i = 0;

cout << "請輸入start：" << endl;
cin>>start;
cout << "請輸入len：" << endl;
cin >> len;

while ((ch = getchar()) != EOF)  //回車後按Ctrl+z鍵再回車，退出迴圈
{
	if (ch != '\n')
	{
		src[i] = (char)ch;
		i++;
	}
}
sum = substr(dst, src, start, len);

cout << src << endl;
cout << dst << endl;
cout << sum << endl;
getchar();
 

}

int substr(char dst[], char src[], int start, int len) { int j;

if (start >= strlen(src) && start < 0 && len < 0)
	dst == NULL;

for (j = 0; j<len; j++)
{
	if (src[start-1] != '\n')  //陣列從0開始的
	{
		dst[j] = src[start-1];
		start++;
	}
}
return len;  //代表了dst中元素的個數

}