???

test.c

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>

typedef char bool;
static const bool false = 0;
static const bool true = 1;

bool primep(uint64_t n) {
	if (n == 2) {
		return true;
	} else if (n % 2 == 0) {
		return false;
	} else if (n < 3) {
		return false;
	} else {
		uint64_t p = 3;
		while (p <= n / p) {
			if (n % p == 0) {
				return false;
			}
			p += 2;
		}
		return true;
	}
}

int main(int argc, char** argv) {
	(void)argc;

	uint64_t n = strtoull(argv[1], NULL, 10);
	if (primep(n)) {
		puts("prime");
	} else {
		puts("composite");
	}
}

test.rs

use std::env;

fn primep(n: u64) -> bool {
    if n == 2 {
        true
    } else if n % 2 == 0 {
        false
    } else if n < 3 {
        false
    } else {
        let mut p = 3u64;
        while p <= n / p {
            if n % p == 0 {
                return false;
            }
            p += 2;
        }
        true
    }
}

fn main() {
    let n: u64 = env::args()
        .skip(1)
        .next()
        .expect("Must be at least 1 arg")
        .parse()
        .expect("Enter valid number");
    if primep(n) {
        println!("prime")
    } else {
        println!("composite")
    }
}