Check whether characters are unique in a string

String-CheckUniqueCharacters.cpp

#inlcude <cstring>
#include <iostream>
#include <set>
#include <cstring>
using namespace std;

bool checkUniqueChars(char *str) {
    char *strP = str;
    set<char> testSet;
    pair<set<char>::iterator, bool> result;
    while (*(strP) != 0) {
        result = testSet.insert(*(strP));
        if (result.second == false) {
            return false;
        }
        strP++;
    }
    return true;
}

bool checkUniqueString(string s) {
    set<char> testSet;
    pair<set<char>::iterator, bool> result;
    for (string::iterator it = s.begin(); it != s.end(); it++) {
        result = testSet.insert(*it);
        if (result.second == false) {
            return false;
        }
    }
    return true;
}

int main() {
    char a[] = "12345abc";
    printf("%d\n", checkUniqueChars(a));
    char b[] = "12345abc123";
    printf("%d\n", checkUniqueChars(b));
    
    string aa = "12345abc";
    printf("%d\n", checkUniqueString(aa));
    string bb = "123452";
    printf("%d\n", checkUniqueString(bb));
}