题解 | #统计字符#

#include <iostream>
#include <string>

using std::cin;
using std::cout;
using std::endl;
using std::string;
int char_num = 0;
int space_num = 0;
int digit_num = 0;
int  other_num = 0;
bool isspace(char ch) {
    return ch == ' ';
}
void count_function(const string& str) {
    for (auto it = str.begin(); it != str.end(); it++) {
        if (isalpha(*it)) { // 判断是否为字母
            char_num ++;

        } else if (isspace(*it)) { // 判断是否为空格
            space_num++;
        } else if (isdigit(*it)) { // 判断是否为数字
            digit_num ++;
        } else { //为其他字符
            other_num++;
        }
    }
    cout <<  char_num  << endl;
    cout <<  space_num  << endl;
    cout <<  digit_num  << endl;
    cout <<  other_num  << endl;
}
int main(void) {
    string str;
    getline(cin, str);
    count_function(str);
}