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#include <limits.h>
#include <stdio.h>
int tadd_ok(int x, int y) {
int positive_overflow = x > 0 && y > 0 && x + y < 0;
int negative_overflow = x < 0 && y < 0 && x + y >= 0;
return !positive_overflow && !negative_overflow;
}
int tadd_buggy(int x, int y) {
int sum = x+y;
printf("sum: %d, sum-x: %d, sum-y: %d", sum, sum-x, sum-y);
return (sum-x == y) && (sum-y == x);
}
/* buggy */
int tsub_ok(int x, int y) {
return tadd_ok(x, -y);
}
void main() {
printf("INT_MIN: %d, %d\n", -(INT_MIN), INT_MIN);
printf("result: %d\n", tadd_ok(10, 100));
printf("result2: %d", tadd_buggy(INT_MAX, 1)); // The sum is a very negative number, when we take the difference with it's parts it just does a negative overflow to get the original parts back.
}
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