如何找到在两个不同数组中交换的值？

Question

我想用一个数组中的赔率和另一个数组中的偶数交换一个数组，同时跟踪计数和被交换的值。

{2, 3, 6}
{1, 4, 7}

will become

{1, 3, 7}
{2, 4, 6}

有 2 次交换，交换的值是 1 &2, 6 & 7.

int main() {
    int a1[3] = { 2, 3, 6 };
    int a2[3] = { 1, 4, 7 };
    int i;
    int swapcount = 0;
    int swapvalue;

    std::cout << "Before swap:\n" << endl;
    std::cout << "Array 1:\n" << endl;
    for (int i = 0; i < 3; i++) {
        cout << " " << a1[i] << endl;

    }
    std::cout << "Array 2:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a2[i] << endl;

    }

    for (int i = 0; i < 3; i++) {
        if (a1[i] % 2 != 1) {
            swapcount++;
            int temp = a1[i];
            a1[i] = a2[i];
            a2[i] = temp;
            swapvalue = i;
        }
    }

    std::cout << "After swap:\n" << endl;
    std::cout << "Array 1:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a1[i] << endl;
    }

    std::cout << "Array 2:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a2[i] << endl;

    }

    std::cout << "swap count: " << swapcount << endl;
    std::cout << "swap value: " << swapvalue << endl;
}

到目前为止，我已经让 swap 和 counter 工作，但我似乎无法弄清楚：

如何查找和存储被交换元素的各个值？ （我只能显示一个值。）

我能得到任何关于如何获取值的提示吗？除了输入和输出流之外，我不允许使用任何其他库。提前谢谢。

Answer 1

创建一个辅助数组swapbool，如果交换完成则设置boolean = 1。

#include<iostream>
using namespace std;
int main() {
    int a1[3] = { 2, 3, 6 };
    int a2[3] = { 1, 4, 7 };
    int swapbool[3] = {0,0,0};
    int i;
    int swapcount = 0;
    int swapvalue;

    std::cout << "Before swap:\n" << endl;
    std::cout << "Array 1:\n" << endl;
    for (int i = 0; i < 3; i++) {
        cout << " " << a1[i] << endl;

    }
    std::cout << "Array 2:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a2[i] << endl;

    }

    for (int i = 0; i < 3; i++) {
        if (a1[i] % 2 != 1) {
            swapcount++;
            int temp = a1[i];
            a1[i] = a2[i];
            a2[i] = temp;
           // swapvalue = i;
            swapbool[i]=1;
        }
    }

    std::cout << "After swap:\n" << endl;
    std::cout << "Array 1:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a1[i] << endl;
    }

    std::cout << "Array 2:\n" << endl;
    for (int i = 0; i < 3; i++) {
        std::cout << " " << a2[i] << endl;

    }

    std::cout << "swap count: " << swapcount << endl;
    for (int i = 0; i < 3; i++) {
        if(swapbool[i] == 1)
        {
            std::cout << "swapvalue1-> " << a2[i] << endl;
            std::cout << "swapvalue2-> " << a1[i] << endl;
        }
    }

    //std::cout << "swap value: " << swapvalue << endl;
}

Answer 2

有很多方法可以做到这一点。最简单的解决方案是将它们存储在std::vector 的std::pair 中：

std::vector<std::pair<int, int>> swapvalues;

然后插入：

swapvalues.emplace_back(val1, val2);

顺便说一句，在您的代码中，您存储的是索引，而不是值。如果要存储索引，请仅使用 std::vector 的整数。

Answer 3

如何找到被交换元素的单个值？

当你交换元素时存储它们的索引：

 int swappedValuesIndex[];

 for (int i = 0; i < 3; i++) {
    if (a1[i] % 2 != 1) {
        // store swapped values' index  
        swappedValuesIndex[swapcount] = i;

        swapcount++;

        int temp = a1[i];
        a1[i] = a2[i];
        a2[i] = temp;
        swapvalue = i;
    }
 } 

 // print swapped values
 for (int i = 0; i < swapcount; i++){
     cout <<"a1["<< swappedValuesIndex[i] <<"]"<< a1[swappedValuesIndex[i]] <<'\n';
     cout <<"a2["<< swappedValuesIndex[i] <<"]"<< a2[swappedValuesIndex[i]] <<'\n';
 }