#include #include int fib(int x) { if (x < 2) { if (x == 0) { return 0; } return 1; } return fib(x - 1) + fib(x - 2); } int main(int argc, char **argv) { if (argc < 2) { fprintf(stderr, "usage: fib [...]\n" "\n" "Return the Nth fibonacci number.\n"); return 0; } for (int n = 1; n < argc; ++n) { int x = atoi(argv[n]); printf("%d: %d\n", x, fib(x)); } return 0; }