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如何在繼續嵌套嵌套循環的同時突破while循環

[英]How to break out of while loop while continuing to iterate in nested for loop

因此我想做的是驗證我的用戶僅使用逗號輸入數字1-4,且不重復。 例如1,2,3,4或2,1,4,3。 我包括一個while循環,以確保用戶輸入正確的信息。 當涉及到for循環時,我感到困惑,因為我不確定是否需要附加的for循環才能使用i和j訪問數組中的該數組? 我真的很困惑,我正在尋求某種幫助。 我目前只有Python經驗。

我意識到,當我跳出while循環以將值輸入到數組中時,一旦返回並詢問用戶下一行的值,for循環的初始化和更新就會重新開始。

我還嘗試將if語句更改為: if (row1Values4x4.charAt(k) > '0' && row1Values4x4.charAt(k) < '5') {但是,這沒有任何意義,因為我想突破當我的for循環遇到的值不在1-4范圍內時,即為循環。

我沒有收到任何錯誤,它沒有按照我想要的方式工作。

import java.util.Scanner;

公共課sudokuPractice {

/**
 * @param args
 */
public static void main(String[] args) {
    // TODO Auto-generated method stub
    int[][] fourArray = { {0,0,0,0}, {0,0,0,0}, {0,0,0,0}, {0,0,0,0} };
            int row = 1;
            int k = 0;
            while (row < 5) 
            {
                String row1Values4x4 = "-1";
                boolean done = false;
                while (!done)
                {
                    Scanner firstRow4x4 = new Scanner(System.in);
                    System.out.println("Please enter four values using commas for row " + row); //this needs to loop
                    row1Values4x4 = firstRow4x4.next();
                    row1Values4x4 = row1Values4x4.replaceAll(" ",""); //this is in case user enters numbers with spaces
                    if (row1Values4x4.length() == 7) {
                        for (k = 0; k < row1Values4x4.length();k++) {
                                if (row1Values4x4.charAt(k) < '0' && row1Values4x4.charAt(k) > '5') {
                                    done = true;
                                } //else {
                                //}
                            }
                    }
                }
                String strArray[] = row1Values4x4.split(",");
                int arraySidesInteger[] = new int[strArray.length];
                for (int i = 0;  i < strArray.length;  i++) {
                    arraySidesInteger[i] = Integer.parseInt(strArray[i]);
                }
                fourArray[row-1] = arraySidesInteger;
                for (int i = 0; i < fourArray.length; i++) {
                    for (int j = 0; j < fourArray.length; j++)
                        System.out.print(fourArray[i][j] + " ");
                    System.out.println();
                }
                row++;
                k++;
                }
}

}

//因為我試圖保留for循環的初始化和更新,所以包含了整數k。

請嘗試一下

公共靜態void main(String [] args){

    int row = 1;
    int k = 0;
    String row1Values4x4 = "-1";
    int[][] arraySidesInteger = { { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 } };

    while (row <= 4) {

        boolean done = false;

        while (!done) {

            Scanner firstRow4x4 = new Scanner(System.in);
            System.out.println("Please enter four values using commas for row " + row); // this needs to loop
            row1Values4x4 = firstRow4x4.next();
            String[] values = row1Values4x4.split(",");

            for (int i = 0; i < values.length; i++) { //Logic to validate the value

                if (Integer.parseInt(values[i]) < 0
                        || Integer.parseInt(values[i]) > 4) {
                    System.out
                            .println("You have entered the value which not fit in the boundary.Please Try again.");
                    done = true;
                    break;
                }
            }

            if (done) { // Loop again to get the row value correctly.
                done = false;
                continue;
            }

            //Adding the value to row
            for (int i = 0; i < values.length; i++) {
                arraySidesInteger[row - 1][i] = Integer.parseInt(values[i]);
            }

            row++;
            done = true;

        }
    }

    //Prints the array
    for (int i = 0; i < arraySidesInteger.length; i++) {
        for (int j = 0; j < arraySidesInteger.length; j++)
            System.out.print(arraySidesInteger[i][j] + " ");
        System.out.println();
    }

}

如果使用標簽,中斷任何級別的循環執行都是很容易的

看例子

int count=0;

A: while(true){
    while(true){
        System.out.println(count++);
        if(count==10){
            break A;
        }
    }
}

第一個循環標記為A,並且break停止執行標記為A的代碼塊的執行

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