#include #include char* printuplow(char* word, char* input){ if(input[0] == '\0'){ return; } input[0] = toupper(input[0]); fprintf(stdout, "%s\n", word); printuplow(word, &input[1]); input[0] = tolower(input[0]); fprintf(stdout, "%s\n", word); printuplow(word, &input[1]); } int main(int argc, char** argv) { if(argc>1) { fprintf(stderr, "%s\n", argv[1]); printuplow(argv[1], &argv[1][0]); } return 0; }