9月5号晚上搜狗笔试

有点晕，其实题目不难，但是自己模拟类的题目做的好少！！ leetcode上刷了270多题，模拟题太少了，每次碰到都有点懵，最后一个dfs的题一个低级错误（倒

第一题：

public class Code_0905_sougou1 {
    public int numberofprize (int a, int b, int c) {
        int l = 0;
        int r = Math.max(a,Math.max(b,c));
        while (l < r){
            int mid = l + r + 1 >> 1;
            if (check(a,b,c,mid)){
                l = mid;
            }else {
                r = mid - 1;
            }
        }
        return l;

    }

    public boolean check(int a,int b ,int c ,int mid){
        int plus = 0;
        if (a >= mid){
            plus += (a - mid);
        }
        if (b >= mid){
            plus += (b - mid);
        }
        if (c >= mid){
            plus += (c - mid);
        }
        int minus = 0;
        if (a <= mid){
            minus += (mid- a);
        }
        if (b <= mid){
            minus += (mid- b);
        }
        if (c <= mid){
            minus += (mid- c);
        }

        return plus / 2 >= minus;
    }

}

第二题：

public class Code_0905_sougou2 {
    public int getHouses (int t, int[] xa) {
        // write code here
        int res = 2;
        int n = xa.length;
        int[] x = new int[n / 2];
        int[] a = new int[n / 2];
        int index = 0;
        for (int i = 0;i < xa.length;i+=2){
            x[index] = xa[i];
            a[index] = xa[i + 1];
        }
        if (n == 1){
            return res;
        }
        for (int i = 0;i < n - 1;i++){
            double lo = (double)x[i] + a[i] / 2.0;
            double hi = (double)x[i + 1] - a[i + 1] / 2.0;
            if (hi - lo < t)continue;
            if (hi - lo == t){
                res++;
            }else {
                res += 2;
            }

        }
        return res;
    }
}

第三题

public class Code_0905_sougou3 {
    long res = 0;
    Set<String> set = new HashSet<>();
    public long getPasswordCount (String password) {
        if (password.equals("")){
            return 0;
        }
        // write code here

        for (int i = 0;i <= 9;i++){
            helper(password,1,new StringBuilder("i"));
        }
        return res;
    }

    public void helper(String password,int index,StringBuilder temp){
        if (index == password.length() ){
            if (!(temp.toString()).equals(password) || !set.contains(temp.toString())){
                set.add(temp.toString());
                res++;
            }
            return;
        }
        helper(password,index + 1 ,
                temp.append((char)((password.charAt(index) + temp.charAt(temp.length() - 1)  / 2) )));
        temp.deleteCharAt(temp.length() - 1);
        helper(password,index + 1 ,
                temp.append((char) ((password.charAt(index) + temp.charAt(temp.length() - 1) + 1) / 2)));
        temp.deleteCharAt(temp.length() - 1);

    }
}