公式解。
Solve by the formula.
ZeroJudge Link (Zh)
#include <stdio.h>
#include <math.h>
main() {
int a, b, c;
while (scanf("%d %d %d", &a, &b, &c) != EOF) {
if (b * b - (4 * a * c) > 0) printf("Two different roots x1=%d , x2=%d\n", (int)((-b+sqrt((double)b*b-4*a*c))/(a*2)), (int)(-b-sqrt(b*b-4*a*c))/(a*2));
else if (b * b - (4 * a * c) == 0) printf("Two same roots x=%d\n", -b/(a*2));
else printf("No real root\n");
}
return 0;
}