java - 如何在迭代多维数组后仅打印一次消息？

Question

Scanner input = new Scanner(System.in);

int numInput;

int number[][] =  {
  {10, 20, 30}, 
  {15, 25, 35}, 
};

System.out.print("\n\tEnter a Number : ");

// Expected input 10

numInput = input.nextInt();
input.nextLine();

for (int i = 0; i < 2; i++) {
  for (int j = 0; j < 3; j++) {
    if (numInput == number[i][j]) {
      System.out.print("\n\tNumber " + numInput + " Found!");
      System.out.print("\n\tOn line " + i + " Column " +j);
    } else {
      System.out.print("\n\tNumber Not Found!");
    }
  }
}

如果用户输入 35，该程序将打印“Number 35 Found!”对于在数组中找到的数字或“未找到数字!”对于数组中的每个其他元素。

我希望它只打印一次。

Answer 1

看起来您需要将“Number not Found”的打印语句移到 for 循环之外。像这样:

Scanner input = new Scanner(System.in);

    int numInput;

    int number[][] =  { {10, 20, 30}, 
                        {15, 25, 35}, 
                    };

System.out.print("\n\tEnter a Number : ");

//Expected input 10

numInput = input.nextInt();
input.nextLine();

boolean found = false;

for (int i = 0; i < 2; i++) {

    for (int j = 0; j < 3; j++) {

        if (numInput == number[i][j]) {

            found = true;
            System.out.print("\n\tNumber " + numInput + " Found!");
            System.out.print("\n\tOn line " + i + " Column " +j);
        }
    }
}

if (!found) {
    System.out.print("\n\tNumber Not Found!");
}

按照您现在的方式，对于每个项目，它总是会打印“找到”或“未找到”。但是，如果您只想在最后打印一次，则需要某种标志来确定是否找到它，如果没有找到，则打印。