void main()
{
int x;
printf("\nIntroduce valor: ");
scanf("%d",&x);
switch(x<0)
{
case 1:
printf("\ny=%d",x*x+5);
break;
case 0:
switch(x<=2)
{
case 1:
printf("\ny=%d",3*x-1);
break;
case 0:
printf("\ny=%d",x*x-4*x+5);
break;
}
}
}