题解 | 统计字符

#include <iostream>
#include <string>
using namespace std;

int main() {
    string str;
    getline(cin,str);
    int len = str.length();
    int a=0,b=0,c=0,d=0;
    for(int i=0 ; i<len ; i++){
        char ch = str[i];
        if((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')){
            a++;
            continue;
        }
        else if(ch == ' '){
            b++;
            continue;
        }
        else if(ch >= '0' && ch <= '9'){
            c++;
            continue;
        }else{
            d++;
        }
    }
    cout << a << endl << b << endl << c << endl << d;
}