#include <stdio.h>
void fn()
{
??? static int x = 1;?? //定義靜態(tài)局部變量
??? x*=2;
??? printf("x=%d\n",x);??? ?
}

int main()
{
??? int i;
??? for(i=0;i<5;i++)
??? {
??????? fn();
??? }
??? extern int x;????? //調(diào)用外部變量
??? printf("x=%d\n",x);
??? return 0;
}
int x=100;

把代碼貼上來啊