This program is based on C++ and the output is [ 0 1 0] how to Z's value 0 ?

Question

#include <iostream>
using namespace std;

int main() {
int x=0,y=0,z=1;
if(z=x<y){
x+=3;
y-=1;
}
else x=y++;
cout<<"x="<<x<<"y="<<y<<"z="<<z;
return 0;
}

Answer 1

well my output is correct i just want to know how the value become zero of (z) ?