// 344. Reverse String #include "leetcode.h" /* * write a function that reverses a string. the input string is given as an * array of characters 's'. you must do this by modifying teh input array in * place with 'O(1)' extra memroy */ void reverseString(char *s, int sSize) { char *ptr = s + sSize - 1, tmp = *s; if (sSize <= 1) return; *s = *ptr; *ptr = tmp; reverseString(s + 1, sSize - 2); } int main() { char *s1 = "hello", *s2 = "Hannah"; reverseString(s1, strlen(s1)); reverseString(s2, strlen(s2)); printf("%s\n", s1); // expect: olleh printf("%s\n", s2); // expect: hannaH }