reverse string

​​https://leetcode.com/problems/reverse-string/​​

Write a function that takes a string as input and returns the string reversed.

Example:
Given s = “hello”, return “olleh”.

1.

char* reverseString(char* s) {
    int i = 0;
    int j = strlen(s) - 1;
    while(i < j) {
        s[i] = s[i] ^ s[j];
        s[j] = s[i] ^ s[j];
        s[i] = s[i] ^ s[j];
        i++;
        j--;
    }
    return s;
}

2.

char* reverseString(char* s) {
    char *start = s;
    char *end = s + strlen(s) - 1;
    for(;start < end; ++start, --end) {
        *start = *start ^ *end;
        *end = *start ^ *end;
        *start = *start ^ *end;
    }
    return s;
}