没看出来
可能是系统问题
我的[AC代码](https://www.luogu.com.cn/record/134500662)
对照一下
```cpp
#include<bits/stdc++.h>
using namespace std;
int a[4];
bool istri(int x,int y,int z){
if(x+y<=z) return false;
return true;
}
bool isrighttri(int x,int y,int z){
if((x*x)+(y*y)==(z*z)) return true;
return false;
}
bool isacutetri(int x,int y,int z){
if((x*x)+(y*y)>(z*z)) return true;
return false;
}
bool isobtusetri(int x,int y,int z){
if((x*x)+(y*y)<(z*z)) return true;
return false;
}
bool isoscelestri(int x,int y,int z){
if(x==y || y==z) return true;
return false;
}
bool equilateraltri(int x,int y,int z){
if(x==y && y==z) return true;
return false;
}
int main(){
cin>>a[1]>>a[2]>>a[3];
sort(a+1,a+4);
if(!istri(a[1],a[2],a[3])){
cout<<"Not triangle"<<endl;
return 0;
}
if(isrighttri(a[1],a[2],a[3])) cout<<"Right triangle"<<endl;
if(isacutetri(a[1],a[2],a[3])) cout<<"Acute triangle"<<endl;
if(isobtusetri(a[1],a[2],a[3])) cout<<"Obtuse triangle"<<endl;
if(isoscelestri(a[1],a[2],a[3])) cout<<"Isosceles triangle"<<endl;
if(equilateraltri(a[1],a[2],a[3])) cout<<"Equilateral triangle"<<endl;
return 0;
}
```
by liuruiqing @ 2023-11-11 14:36:46
@[liuruiqing](/user/1118614)
我知道了，我的代码的第34行
```cpp
if (arr[0] == arr[2] || arr[1] ==arr[2] || arr[0] == arr[2])
```
判断等腰三角形的第三个条件写错了，应该是
```cpp
if (arr[0] == arr[2] || arr[1] ==arr[2] || arr[0] == arr[1])
```
by XTTian @ 2023-11-11 15:51:30
@[XTTian](/user/1165215) 问题已解决
by XTTian @ 2023-11-11 15:52:13