n个人数3找出最后一个剩余人号码的改进版

#include <stdio.h>

#include <stdlib.h>

int LastNum(int n)

{

int i = 0;

int out = 0; //退出的人数

int num = 0; //报数

int lastnum = 0;

int *a;

if(n <= 0){

printf("Person num is illegal\n");

return -1;

}

a=(int*)malloc(n*sizeof(int));

for (i = 0; i < n; i++)

{

a[i] = 1;

}

i = 0;

while (out != n-1)

{

if (a[i] == 1)

{

num++;

}

if (num == 3)

{

a[i] = 0;

num = 0;

out++;

}

i++;

if (i == n)

{

i = 0;

}

}

for (i = 0; i < n; i++)

{

if (a[i] == 1)

{

lastnum = ++i;

break;

}

}

return lastnum;

}

void main()

{

int n;

printf("Please input total person number:");

scanf("%d", &n);

printf("The last person number is %d\n", LastNum(n));

}