public class Rabbit { 
 	public static void fun(int t) { 
 		int r1 = 0, r2 = 2, i=0,temp = 0; 
 		if (t  < 1) 
 			return; 
 		while (i <t) { 
 			System.out.println("第"+(i+1)+"月:"); 
 			System.out.println(r2); 
 			temp = r1; 
 			r1 = r2; 
 			r2 = temp + r2; 
 			i++; 
 		} 
 	} 
  
 	public static void main(String[] args) { 
 		System.out.println("兔子数目："); 
 		fun(12);//参数代表第多少个月 这里是12个月 
 	} 
 }

public class RabitCounter {
    public static void main(String[] args){
        int month=7;
        int result=0;
        int[] currArray={0,0,0};
        int[] prevArray={1,1,2};
        int end=0;
        int pos=0;
        if((month/3)*3<month){
            end=month/3;
            pos=month-((month/3)*3)-1;
        }else{
            end=month/3-1;
        }
        if(month<1){
            result=0;
        }else if(month<=2){
            result=1;
        }else if(month==3){
            result=2;
        }else{
            for(int i=1;i<=end;i++){
                currArray[0]=prevArray[2]+prevArray[0];
                System.out.println(currArray[0]);
                currArray[1]=currArray[0]+prevArray[1];
                System.out.println(currArray[1]);
                currArray[2]=currArray[1]+prevArray[2];
                System.out.println(currArray[2]);
                result=currArray[2];
                prevArray=currArray;            
                System.out.println("=================="+i+"================");
            }
            result=currArray[pos];
        }
        
        System.out.println("到第"+month+"个月共"+result*2+"只兔子");
    }
}