在数组c ++中打印重复数字的数量

Question

我想知道如何从随机生成的数组中打印重复数字的数量，数组大小为 10，数字范围为 1 - 10。

示例： 数组1：1 7 6 5 6 7 8 10 9 8

图案数量：3

（因为它包括；2 个六、2 个七、2 个八）

到目前为止，我已经完成了我的代码

#include <iostream>
#include <iomanip>
#include <string>
#include <time.h>
#include "Source.h"
#include <algorithm>   
using namespace std;

void main()
{
    //START OF PROGRAM CODE\\

    //Declaritions\\

    const int ArraySize = 10;
    int arrayMain[ArraySize];
    int array1[ArraySize];
    int i = 0;
    int j = 0;
    int k = 0;


    //End of Declairations\\

    //Store Random Number in Array\\

    srand((unsigned)time(0));

    for (i = 0; i < 10; i++)
     {
        arrayMain[i] = (rand() % 10) + 1;
        array1[i] = arrayMain[i];  //Copy mainarray to array1


     }  

    for (j = 0; j != ArraySize; j++)
     {
        sort(array1, array1 + ArraySize); //Sort the array

     }


        //End of Store Random Number in Array\\
        //Program Output\\


    cout << "ArrayMain: " << arrayMain[0] << " " << arrayMain[1] << " " << arrayMain[2] << " " << arrayMain[3] << " " << arrayMain[4] << " " << arrayMain[5] << " " << arrayMain[6] << " " << arrayMain[7] << " " << arrayMain[8] << " " << arrayMain[9] << " " << endl;
    cout << "Array1: " << array1[0] << " " << array1[1] << " " << array1[2] << " " << array1[3] << " " << array1[4] << " " << array1[5] << " " << array1[6] << " " << array1[7] << " " << array1[8] << " " << array1[9] << " " << endl;
    //cout << "Number of Patterns: " << <DATA TO INPUT> << endl;

    //END OF PROGRAM CODE\\


}

Answer 1

有一个非常简单的模式。您可以使用大小等于可能随机数范围的数组（我将使用向量）

//creates a vector ArraySize big with all elements initialized to 0
std::vector<int> results(ArraySize, 0);

然后，遍历你的循环并使用随机数作为索引并增加值

for(int i = 0; i < 10; i++)
  results[(rand() % 10)]++;

最后，计算有多少种模式

std::cout << "Number of patterns: ";
std::cout << std::count_if(results.begin(), results.end(), [](int i){return i > 1;});
std::cout << std::endl;