java笔试-米哈游秋招笔试-9.19（顺时针打印，正则匹配（.\*\+））

java通关整理汇总-Java基础、计算机网络、数据库、设计模式、框架、算法模板、笔试

---

1.A-Z顺时针打印
输入m，n，然后顺时针把A-Z打印到数组中

package mihayou2;

import java.util.Scanner;

/**
 * @author liu
 * @Description
 */
public class main1 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int m = sc.nextInt();
        int n = sc.nextInt();
        char[][] ch = new char[m][n];

        char[] a = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
        char[] b = new char[n*m];

        int top = 0,bottom = m-1,left = 0,right = n-1;
        int k = 0;


        while (true){
            //从左到右
            for(int i = left;i<=right;i++){
                ch[top][i] = a[(k%26)];
                k++;
            }
            if(++top >bottom) break;

            //从上到下
            for(int i = top;i<=bottom;i++){
                ch[i][right] = a[(k%26)];
                k++;
            }
            if(--right <left) break;

            //从右到左
            for(int i = right;i>=left;i--){
                ch[bottom][i] = a[(k%26)];
                k++;
            }
            if(--bottom <top) break;

            //从下到上
            for(int i = bottom;i>=top;i--){
                ch[i][left] = a[(k%26)];
                k++;
            }
            if(++left >right) break;
        }

        for(int i = 0;i<m;i++){
            for(int j = 0;j<n;j++){
                System.out.print(ch[i][j] + " ");
            }
            System.out.println();
        }

    }
}

2.正则匹配（. * +）

package mihayou2;

import java.util.Scanner;

/**
 * @author liu
 * @Description
 */
public class main2 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        String p = sc.next();
        System.out.println(isSubString(s,p));

    }
    private static boolean isSubString(String s,String p){

        if(s==null||p==null){
            return false;
        }
        int rows = s.length();
        int columns = p.length();
        boolean[][] dp = new boolean[rows+1][columns+1];

        dp[0][0] = true;
        for(int j = 1;j<columns+1;j++){
            if(p.charAt(j-1) == '*' && dp[0][j-2]){
                dp[0][j] = true;
            }
        }


        for(int i = 1;i<rows+1;i++){
            for(int j = 1;j<columns+1;j++){
                char nows = s.charAt(i-1);
                char nowp = p.charAt(j-1);
                if(nows == nowp){
                    dp[i][j] = dp[i-1][j-1];
                }else {
                    if (nowp == '.') {

                        dp[i][j] = dp[i-1][j-1];
                    }else if(nowp == '*'){
                        if(j>=2){
                            char nowLast = p.charAt(j-2);
                            if(nowLast == nows||nowLast=='.'){
                                dp[i][j] = dp[i-1][j]||dp[i][j-1];
                            }
                            dp[i][j] = dp[i][j]||dp[i][j-2];
                        }
                    }else if(nowp == '+'){
                        if(j>=2){
                            char nowpLast = p.charAt(j-2);
                            if(nowpLast == nows||nowpLast == '.'){
                                dp[i][j] = dp[i-1][j]||dp[i][j-1];
                            }
                        }
                    }else {
                        dp[i][j] = false;
                    }
                }
            }
        }
        return dp[rows][columns];
    }
}