#include <stdio.h>

void classify_triangle(int a, int b, int c) {
    if (a <= 0 || b <= 0 || c <= 0 || (a + b <= c) || (a + c <= b) || (b + c <= a) {
        printf("Invalid input\n");
   } 
   else if(a == b && b == c) {
        printf("Equilateral\n");
   }
   else if(a == b || b == c || a == c) {
        printf("Isosceles\n");
   }
   else {
       printf("Scalene\n");
   }
    
}
int main() {
    int a = 3, b = 4, c = 5;
    classify_triangle(a, b, c);
    return 0;
}