Question

我有一个只有2行N列的二进制矩阵。

第一行元素的总和为A，第二行元素的总和为B。

列的总和存储在数组C中。

If A = 3, B = 2, C = [2,1,1,0,1] Then output is "11001,10100"

Explanation:
11001 = sum of 1st row is A = 3
10100 = sum of 2nd row is B = 2

21101 --> This is column sum which indicates Array C.

另一个例子：

If A = 2, B = 3, C = [0,0,1,1,2] Then output is "NO"

我写了下面的程序，该程序适用于上述测试用例，但是当我在面试中运行它时，它仅通过了40％的测试用例，请您能帮助我解决这个问题，该程序中的错误是什么？纠正这个问题？

public static String process(int A, int B, int[] C) {
    int total = 0;
    for (int val : C) {
        total = total + val;
    }
    // Sums do not match so matrix is not possble
    if (total != A + B) {
        return "NO";
    } else {
        String first = "", second = "";

        boolean flag = true;
        for (int i = 0; i < C.length; i++) {
            // Both the columns must be 1
            if (C[i] == 2) {
                first += "1";
                second += "1";
            } else if (C[i] == 0) {
                // Both the columns must be 0
                first += "0";
                second += "0";
            } else {
                // Any one if the columns should be 1
                if (flag) {
                    first += "1";
                    second += "0";
                } else {
                    first += "0";
                    second += "1";
                }
                flag = !flag;
            }
        }
        return first + "," + second;
    }
}

Answer 1

几乎，但是这里出了问题：

// Any one if the columns should be 1

仅考虑这将意味着您的两个矩阵将满足C提供的条件，但不能满足A和B的条件，因为您只是为情况C[i] == 1进行了交替

此中断最简单的情况：A = 2，B = 0和C = [1,1]。您的程序将打印"10,01"，而应打印"11,00"。

因此，诀窍是：处理了简单的C[i] == 0和C[i] == 2案例之后，您必须弄清楚在第一行和第二行中还需要多少个1

编辑：可能的解决方案是：

boolean flag = true;
int currentTopRowSum = 0;
for (int i = 0; i < C.length; i++) {
// Both the columns must be 1
  if (C[i] == 2) {
    first += "1";
    second += "1";
  } else if (C[i] == 0) {
    // Both the columns must be 0
    first += "0";
    second += "0";
  } else {
    //This is where it went wrong, so I changed this.
    if (currentTopRowSum < A) {
      first += "1";
      second += "0";
      currentTopRowSum++;
    } else {
      first += "0";
      second += "1";
    }
  }
}

简而言之，您跟踪第一行的总和，如果尚未达到该标准，则在其中加上"1"。如果有的话，请将其添加到底部一行。

对于给定的行和列总和，检查二进制矩阵是否仅存在2行

1 个答案: