用指针统计字符串中的大写字母小写字母空格以及数字
时间: 2024-03-24 13:12:25 浏览: 19
可以指针遍历字符串中的每个字符,并根据 ASCII 码判断属于哪一类。
以下是一个示例代码:
```c++
#include <iostream>
using namespace std;
int main() {
char str[] = "Hello World 123";
char *p = str;
int upper = 0, lower = 0, space = 0, digit = 0;
while (*p != '\0') {
if (*p >= 'A' && *p <= 'Z')
upper++;
else if (*p >= 'a' && *p <= 'z')
lower++;
else if (*p == ' ')
space++;
else if (*p >= '0' && *p <= '9')
digit++;
p++;
}
cout << "Uppercase letters: " << upper << endl;
cout << "Lowercase letters: " << lower << endl;
cout << "Spaces: " << space << endl;
cout << "Digits: " << digit << endl;
return 0;
}
```
输出结果为:
```
Uppercase letters: 2
Lowercase letters: 8
Spaces: 2
Digits: 3
```