HCF program with multiple numbers in c

#include<stdio.h>
int main(){
int x,y=-1;
printf("Insert numbers. To exit insert zero: ");

while(1){
scanf("%d",&x);
if(x<1)
break;
else if(y==-1)
y=x;
else if (x<y)
y=gcd(x,y);
else
y=gcd(y,x);
}

printf("GCD is %d",y);

return 0;
}

int gcd(int x,int y){
int i;
for(i=x;i>=1;i--){
if(x%i==0&&y%i==0){
break;
}
}
return i;
}