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/** * 二分查找，等于某个值的位置,非递归 * @param data */public static int binarySearch1(int[] data,int val){    if(data == null || data.length ==0){        return -1;    }    int low = 0;    int high = data.length;    while (low <= high){        int midden = low+((high - low)>>1);        if(data[midden]>val){            high = midden -1;        }else if(data[midden]
   
     high) return -1;    int midden = low +((high-low)>>1);    if(data[midden]>val){        return searchInternally(data,low,midden - 1,val);    }else if(data[midden]
    
     >1);        if(data[midden]>val){            high = midden -1;        }else if(data[midden]
     
      >1);        if(data[midden]>val){            high = midden - 1;        }else if(data[midden]
      
       >1);        if(data[midden]>=val){            if(midden == 0 || data[midden - 1]
       
        >1);        if(data[midden]<= val){            if(midden == high || data[midden+1]>val)return midden;        }else {            high = midden - 1;        }    }    return -1;}public static void main(String[] args) {    int[] data = {1,2,3,4,5,6,7,8,9};    int val = 4;    int position  = binarySearch1(data,val);    System.out.println(val+" 的位置为:"+position);    System.out.println(val+" 的位置为:"+searchInternally(data,0,data.length,val));    int[] data2 = {1,2,3,4,5,5,5,6};    val = 5;    System.out.println("第一个 "+val+" 出现的位置为:"+searchFirstVal(data2,val));    System.out.println("最后一个 "+val+" 出现的位置为:"+searchLastVal(data2,val));    int[] data3 = {1,2,3,4,6,7};    val = 5;    System.out.println("第一个大于或等于 "+val+" 出现的位置为:"+searchGtEVal(data3,val));    val = 7;    System.out.println("最后一个小于或等于 "+val+" 出现的位置为:"+searchGtEVal(data3,val));}
       
      
     
    
   

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