二分查找、二叉搜索

查找——折半查找（二分查找、二叉搜索）

简单的折半查找方法

public static int binSearch(int[] arr, int first ,int last, int target){    int mid;    int midValue;    while(first < last){        mid = (first + last) / 2;        midValue = arr[mid];//查找成功        if(target == midValue){            return mid;        }else if(target < midValue){            last = mid;        }else{            first = mid;        }    }    return -1;//查找失败}
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泛型二叉搜索方法

public static <T> extends Comparable<? super T>int binSearch(T[] arr, int first, int last, T target){    int mid;    T midValue;    while(first < last){        mid = (first + last) / 2;        midValue = arr[mid];        if(target.compareTo(midValue) == 0){            return mid; //查找成功        }else if(target.compareTo(midValue) < 0){            last = mid;        }else{            first = mid;        }    }    return -1; // 查找失败}
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