(c++) 将数组索引和它包含的元素从 function 移动到 function

Question

I have to create multiple functions (no limit), main should create 75 random numbers. range{0 to 100}. and in another function i need to add odd index elements(call it s2) and in another function add the even(s1). and another function that will print the answers to s1 and s2. the actual question i was given:

Using C++ code, write a program to compute the product of the sums S1 and S2 of the even (indexes 0, 2, 4, 6, 8, ...) and odd (indexes 1, 3, 5, 7, 9, ...) elements, respectively, of a vector (or array) A of n = 75 random integers in the range [0,100]. First, A is created and initialized using 75 random integers in the function main. Secondly, a function even_sum receives, as parameters, A and n, and computes and returns S1. Thirdly, a function odd_sum receives, as parameters, A and n, and computes and returns S2. Lastly, a function finalize receives, as parameters, S1 and S2 and computes and prints the product of S1 and S2.

so far, i finished main, inside it creates completly random numbers that are unique. i am having trouble moving the vales from main to another function. hope this make sense. I am very new to coding, and would love inputs or critics to learn from.

#include<iostream>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <stdbool.h>
using namespace std;


void odd()

{
    
}

void fill(int array[], int length, int min, int max);//inital
int main()
{
    srand (unsigned(time(NULL)));
    cout<<"random 75 numbers are following: \n";
    int a[75];
    //void fill(int array[], int length, int min, int max);
    fill(a, 75, 1, 100);
    
    for (int i=0;i<75;i++)
    {
        printf("a[%d] = %d\n", i, a[i]);
            }
    
  
}

    void fill(int array[], int length, int min, int max)
{
        int new_num;
        bool unique;//verify if the new number is unique compared to array
        
        for(int i=0; i<length; i++)//generate number, make sure its unique
        {
            do
            {
                new_num=(rand()%(max-min+1))+ min;
                unique= true;
                
                for(int j=0; j<i;j++)
                    if (array[j]==new_num)

                        unique= false;
            }
            while(!unique);
            
            array[i]= new_num;
            void odd();
    }
   
  // game plan is to go from main to odd fuction to even to finialize and in finalize, cout/print the sums
}

Answer 1

The problem asks you to compute two sums that depends on A and then multiply those results, so in this situation, you may want to modularize your tasks by thinking those sums as "functions". Let me explain

1. You want to compute the sum of odd-indexed numbers of A, so you take into account 2 main parameters: A and its length, right? So let's do that:

// Here, you will define the odd_sum function
int odd_sum(int array[], int length)
{
    // Here, you compute the odd-indexed values and accumulate them,
    // For example, you may declare a
    // int sum = 0;
    // and start adding the values within a for loop
    // Finally you return sum
    return sum;
}

2. You want to compute the sum of even-indexed numbers of A, so you do the same as the previous one but with slight variations:

// Here, you will define the even_sum function
int even_sum(int array[], int length)
{
    // Here, you compute the even-indexed values and accumulate them,
    // For example, you may declare a
    // int sum = 0;
    // and start adding the values within a for loop
    // Finally you return sum
    return sum;
}

3. Finally, you want to get those values and multiply them, so it may not be difficult to do it inside your main function:

int odd_sum(int array[], int length);
int even_sum(int array[], int length);

int main()
{
    int a[75];
    // Do your generating stuff
    int oddSum = odd_sum(a, 75);
    int evenSum = even_sum(a, 75);
    int product = oddSum * evenSum;
    printf("Product is %d", product);
}