I try to run this program to check the number is Pythagorean triples or not but this code doesn't work out. What I did wrong with this code?

#include<iostream>
#include<algorithm>
using namespace std;

I try to run this program to check the number is Pythagorean triples or not but this code doesn't work out. What I did wrong with this code?

bool check( int x, int y, int z){
    int a = max(x , max(y,z));

I try to run this program to check the number is Pythagorean triples or not but this code doesn't work out. What I did wrong with this code?

    int b;
    int c;

    if(a==x){
        b==y;
        c==z;
    }
    else if(a==y){
        b==x;
        c==z;
    } else{
        b==x;
        c==y;
    }
    if(a*a  ==  b*b + c*c){
        return true;
    }
     else{
        return false;
    }
}


int32_t main(){
    int  x,y,z;
    cin>>x>>y>>z;

    if (check(x,y,z)){
        cout<<"Pythagorean Triplet";
    } else{
        cout<<"Not a pythagorean Triplet";
    }
    return 0;
}

I try to run this program to check the number is Pythagorean triples or not but this code doesn't work out. What I did wrong with this code?