```cpp
#include <cstdio>
#include <algorithm>
using namespace std;
int a, b, c;
int main() {
scanf("%d%d%d", &a, &b, &c);
int d[4] = {0, a, b, c};
sort(d + 1, d + 4);
if(d[1] + d[2] <= d[3]) {
printf("Not triangle\n");
return 0;
}
if(d[1] * d[1] + d[2] * d[2] == d[3] * d[3]) printf("Right triangle\n");
else if(d[1] * d[1] + d[2] * d[2] > d[3] * d[3]) printf("Acute triangle\n");
else if(d[1] * d[1] + d[2] * d[2] < d[3] * d[3]) printf("Obtuse triangle\n");
if(a == b || b == c || a == c) printf("Isosceles triangle\n");
if(a == b && b == c) printf("Equilateral triangle\n");
return 0;
}
```
by zsfzmxl @ 2023-11-18 10:08:21
````cpp
#include <bits/stdc++.h>
using namespace std;
int main(){
int a,b,c,e,f,g;
cin>>a>>b>>c;
if(a>b) swap(a,b);
if(a>c) swap(a,c);
if(b>c) swap(b,c);
e=a*a;f=b*b;g=c*c;
if(c>=a+b){ cout<<"Not triangle\n";return 0;}
if(e+f==g) cout<<"Right triangle\n";
if(e+f>g) cout<<"Acute triangle\n";
if(e+f<g) cout<<"Obtuse triangle\n";
if(a==b||a==c||b==c) cout<<"Isosceles triangle\n";
if(a==b&&b==c) cout<<"Equilateral triangle\n";
return 0;
}
``````
by gaojizhe05 @ 2023-11-18 10:09:12
````cpp
if(a[0] + a[1] < a[2]){
cout << "Not triangle";
}
````
-->\
````cpp
if(a[0] + a[1] < a[2]){
cout << "Not triangle";
return 0;
}
``````
by gaojizhe05 @ 2023-11-18 10:11:10
@[damuzhi](/user/1127424)
by gaojizhe05 @ 2023-11-18 10:13:21