Name Validation [THCS4 N1]

//Tran Viet Anh - 10:04PM
#include<iostream>

using namespace std;

string valid(string s)
{
    string result = "";
    int i = 0, _end = s.length() - 1;
    while (s[i] == ' ') i++;
    while (s[_end] == ' ') _end--;
    if (s[i] >= 97 && s[i] <= 122) result += s[i] - 32;
    else result += s[i] - 32;
    for (int j = i + 1; j <= _end; j++)
        if (s[j] != ' ')
            if (s[j - 1] == ' ')
                if (s[j] >= 97 && s[j] <= 122) result += s[j] - 32;
                else result += s[j];
            else
                if (s[j] >= 65 && s[j] <= 90) result += s[j] + 32;
                else result += s[j];
        else
            if (s[j - 1] != ' ') result += ' ';
    return result;
}

int main()
{
    string s; getline(cin,s);
    cout << valid(s);
}