这2个程式结果为什么不一样!!!!!!
main(){
int day,x1,x2;
for(day=9;day<0;day--)
{ x2=1;
x1=(x2+1)*2;
x2=x1;
}
printf("%d",x1);
getch();
}
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main()
{
int day,x1,x2;
day=9;
x2=1;
while (day>0)
{
x1=(x2+1)*2;
x2=x1;
day--;
}
printf("%d",x1);
getch();
}