main()
{
int x;
x=10;
y=2+x++;
printf("value of x is %d",x++);
printf("Value of x after increment is %d",y);
}

In function 'main':
Line 5: error: 'y' undeclared (first use in this function)
Line 5: error: (Each undeclared identifier is reported only once
Line 5: error: for each function it appears in.)