题解 | #统计字符#

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

int main() 
{
    string s;
    getline(cin, s);
    int letternum = 0;
    int blanknum = 0;
    int num = 0;
    int othernum = 0;
    for (int i = 0; i < s.size(); i++)
    {
        if (((s[i] >= 'a') && (s[i] <= 'z')) || ((s[i] >= 'a') && (s[i] <= 'Z')))
        {
            letternum++;
        }
        else if (s[i] == ' ')
        {
            blanknum++;
        }
        else if ((s[i] >= '0') && (s[i] <= '9'))
        {
            num++;
        }
        else
        {
            othernum++;
        }
    }
    cout << letternum << endl;
    cout << blanknum << endl;
    cout << num << endl;
    cout << othernum << endl;
    return 0;
}