How do I convert C++ code to C code

#include <iostream>
#include <chrono>
#include <ctime>
#include "SHA256.h"

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

	for (int i = 1; i < argc; i++) {
		SHA256 sha;
		sha.update(argv[i]);
		uint8_t* digest = sha.digest();

		std::cout << SHA256::toString(digest) << std::endl;

		delete[] digest;
	}

	return EXIT_SUCCESS;
}