#include #include #include int strcasecmp(const char* s1, const char* s2) { int i = 0; char c1, c2; while (s1[i] != 0 && s2[i] != 0) { c1 = tolower(s1[i]); c2 = tolower(s2[i]); if (c1 != c2) return s1[i] - s2[i]; i++; } return s1[i] - s2[i]; } int main(int argc, char* argv[]) { if (argc < 3) perror("not enough args"); printf("%d\n", strcasecmp(argv[1], argv[2])); }