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#include<stdio.h>
#define nmax 50
int main(void)
{
int i=0,k=0,m=0,n,num[nmax],*p;
printf("please input the total of numbers:");
scanf("%d",&n);//获取总数，不大于nmax
p=num;//num的地址给了p
for(i=0;i<n;i++)
{
*(p+i) = i+1;
}//给数组的n个元素赋值
i=0;
while(m<n-1)
{
if(*(p+i)!=0)
k++;
if(k==3)
{
*(p+i) = 0;
k = 0;
m++;
}
i++;
if(i==n)
i = 0;
}
while(*p==0)
p++;
printf("%d is left\n",*p);
}
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