排成一圈数3退出最后一人位置问题--C语言谭浩强版练习8.5

有n个人围成一圈，顺序排号。从第一个人开始报数（从1到3报数），凡报到3的人退出圈子，问最后留下的是原来第几号位置

 

 

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E8.5

 

Plan:可以不循环喊1到3，用总数是不是3的倍数代替

 

CREATE----------------------------

By:     Idooi Liu

Time:   2015/10/15-1500

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#include <stdio.h>
#include <stdlib.h>

int expThree(int n, int manArray[]);

int main(void)
{
    int nMan;       //How many people
    char *pMan;     //The array
    int siteLast;   //The last person's site
    int i;

    printf("Please input how many people:\n");
    scanf("%d", &nMan);

    pMan=malloc(nMan*sizeof(char));

    //Assignment
    for(i=0; i<nMan; i++)
        *(pMan+i)='Y';

    siteLast=expThree(nMan, pMan);
    printf("The last one\'s site is %d\n", siteLast);

    free(pMan);
    return 0;
}

int expThree(int n, int manArray[])
{
    int i, j;
    int siteLast;   //The last person's site
    int flag=0;     //Count off
    int k;

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

        //For check how many people last
        for(j=0; j<n; j++)
        {
            if(manArray[j]=='Y')
                k++;
            siteLast=j;
        }
        if(k==1)        //Only one person
            break;

        if(manArray[i]=='Y')
        {
            flag++;     //The person who in the team take the next number
            //If the person's number is pisible by 3, take out of the team
            if(flag%3==0)
                manArray[i]='N';
        }
    }
    return siteLast;
}