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#include <stdio.h>
#include <sys/types.h>
#include <stdlib.h>
#include <limits.h>

/*
 * Determine whether arguments can be added without overflow
 * Two's complement
 *
 * Returns 1 if arguments can be added without overflow
 * 0 otherwise
 */
int tadd_ok(int x, int y)
{
//	if ((x > 0 && y > 0) && (x + y) < 0 ||
//	    (x < 0 && y < 0) && (x + y) > 0)
//		return 0;
//	else if ((x < 0 && y < 0) && (x + y) > 0)
//		return 0;
//	else
//		return 1;

	/* Negative overflow can also be 0 */
	return !(((x > 0 && y > 0) && (x + y) < 0) ||
		((x < 0 && y < 0) && (x + y) >= 0));
}

int uadd_ok(unsigned x, unsigned y)
{
	return ((x + y) >= x);
	//return ((x + y) < x) ? 0 : 1;
}



int main(void)
{
	unsigned a = 5;
	unsigned b = 0;
	int X = INT_MIN;
	int Y = INT_MIN;
	int ret;

	ret = uadd_ok(a, b);
	printf("SUM: %u\n", a + b);
	printf("Return is: %d\n", ret);

	ret = tadd_ok(X, Y);
	printf("Signed values\n");
	printf("SUM: %d\n", X + Y);
	printf("Return is: %d\n", ret);
	return 0;
}