Represent an integer in binary format

bitsrepr.c

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

void dtob(unsigned int word, char* text) {
    for (int bit = 31; bit >= 0; bit--) {
		int shift = word >> bit;
		printf("%d", shift & 1);
    }
    printf(" (%s: %d)\n", text, word);
}

int main(int argc, char *argv[]) {
	// gcc -o tester tester.c <num>
	int x = 5;

	if (argc == 2) {
		x = atoi(argv[1]);
	}

	dtob(x, "x");
	dtob(~x + 1, "-x");
	dtob(-1, "-1");
}

11111111111111111111111111110110 (x: -10)
00000000000000000000000000001010 (-x: 10)
11111111111111111111111111111111 (-1: -1)