#include<stdio.h>
void classify_triangle(int a, int b, int c){
    if(a <= 0 || b <= 0 || c <= 0){
        printf("Invalid Input\n");
        return;
    }
    if(a + b <= c || a + c <= b || b + c <= a){
        printf("Invalid Input\n");
        return;
    }
    else if(a == b || b == c || a == c){
        printf("Isosceles\n");
    }
    else{
        printf("Scalene\n");
    }
}
int main(){
    int n1, n2, n3;
    scanf("%d %d %d", &n1, &n2, &n3);
    classify_triange(n1, n2, n3);
    return 0;
}