看不懂

#include <stdio.h>int Coconut(int n);int main(){               printf("y = %d\n",Coconut(5));return 0;}int Coconut(int n){int i = 1;float x=1,y;y = n*x+1;do{    y=y*n/(n-1)+1;    i++;    if(y != (int)y)    {        x++;        y=n*x+1;        i=1;    }    }while(i<n);    return (int)y;}