#include <stdio.h>
int main() {
int a, b, c;
printf("Enter the length of three sides: ");
scanf("%d %d %d", &a, &b, &c);
if (a == b && b == c) printf("Equilateral triangle.");
else if (a == b || b == c || a == c) printf("Isosceles triangle.");
else printf("Scalene triangle.");
}