数组中出现次数超过一半的数字

	public static int moreHalfSimple(int[] num)
	{
		
		int count =1;
		int index;
		int result=num[0];
		for(index = 1;index<num.length-1;index++)
		{
			
			if(count==0)
			{
				result = num[index];
				count=1;
			}
			if(result != num[index])
				count--;
			else 
				count++;
			
		}
		 
		
		if(!checkHalf(num,result))
		{
	            result=-1;//没找到返回-1
		}
		return result;
			 
	}

        //判断数字是否出现了数组一半以上的长度
	private static boolean checkHalf(int[] num, int result) {
		 
		int count=0;
		for(int i =0;i<num.length;i++)
		{
			if(num[i] == result)
				count++;
		}
		if(count*2 <=num.length)
			return false;
		return true;
	}

private static int partition(int []num,int start,int end)
	{
		if(num==null || num.length ==0)
			return -1;
		
		int s = num[end];
		int minIndex=start-1;
		int maxIndex=start; 
	 
		for(;maxIndex<end;maxIndex++)
		{
			if(num[maxIndex] <= num[end])
			{
				minIndex++;
				
				swap(num,minIndex,maxIndex);
				
			}

		}
		swap(num,minIndex+1,maxIndex);
	
		
		return minIndex+1;
	}
	
	private static void swap(int[] num ,int a ,int b)
	{
		int temp = num[a];
		num[a] = num[b];
		num[b] = temp;
	}
 
	static boolean inputflag= false;//全局变量记录是输入无效还是没找到
	public static int moreThanhalf(int[] num,int start,int end)
	{
		if(num ==null || num.length==0 ||start>end)
		{
		        inputflag=true;
			return -1;  inputflag为true且返回-1，说明输入无效

		}
		int result=0;
		int middle = num.length >> 1;
		int index;
		index = partition(num, start, end);
		
		while(index != middle)
		{
			if(index>middle)
			{
				index =partition(num, start, index-1);
			}
			else 
			{
				index = partition(num, index+1, end);
			}
		
		}
		 result = num[middle];
		if(!checkHalf(num,result))
		{
			 result =0;//返回0且inputFlag为false说明没找到

		}
		return result; 
		
	}
	
	private static boolean checkHalf(int[] num, int result) {
		 
		int count=0;
		for(int i =0;i<num.length;i++)
		{
			if(num[i] == result)
				count++;
		}
		if(count*2 <=num.length)
		{	inputflag=false;
                          return false; 
                }
               return true;
               }

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