#include<stdio.h>

int main(){
    int a,b,c,tmp;
    while(~scanf("%d%d%d",&a,&b,&c)){
        if(a>b){
            tmp=a;a=b;b=tmp;
        }
        if(b>c){
            tmp=b;b=c;c=tmp;
        }
        if(a*a+b*b==c*c) printf("直角三角形\n");
        else if(a*a+b*b>c*c) printf("锐角三角形\n");
        else printf("钝角三角形\n");
    }
    return 0;
}