problem I will read in a second file into the array how d

** problem - I will read in a second file into the array - how do I compare pixel i,r,g in order to combine the two images into 1 image?c++

#include <iostream>
#include <fstream>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <stdio.h>

using namespace std;

int heigth = 0; //initialize variables
int width = 0;
const int amount = 3;

struct pixelimage // create structure to hold image
{
    int **tempa;
    int r,g,b;
    int rows, cols;

}image1;// structure type pixelimage

int main()
{
    const int amount = 3; //variable r b g
    string sentence, filename, mgicnum; //variable to hold comments, magic number and filename
    int width, height, maxCol;
    ifstream inputFile; //open input and output file
    ofstream outputFile;
    outputFile.open(\"Alec001.ppm\", ios:: in | ios::out); //file to open in irfan
    cout << \"enter a file \" << endl; // user prompt
    cin >> filename;
    inputFile.open(\"lec001.ppm\");
    //image2 = inputfile.open(image2.ppm)
    inputFile >> mgicnum;//read in header information
    while ((inputFile>>ws).peek() == \'#\') { inputFile.ignore(4096, \'\ \');}

    inputFile >> height;
    inputFile >> width;
    inputFile >> maxCol;

    cout << mgicnum ;
    cout << height ;
    cout << width ;
    cout << maxCol<<endl;
    outputFile << mgicnum << endl;
    outputFile << sentence << endl;
    outputFile << height << \" \" << width <<endl;
    outputFile << maxCol <<endl;

    int totalsize = (height * width * amount); // total size of array
    int *tempa;
    int i;
    //modified
    tempa = (int *)malloc(sizeof(int)* totalsize);// allocate memory so program does not crash **** error here invalid conversion
     //
            for (i =0; i < totalsize; i++) {
            tempa[i] = 0;
    }
    free(tempa);
  
    for (int i = 0; i < totalsize; i++){
    inputFile >> (image1.r, image1.g, image1.b);//modified
   }

}

Solution

you need to create another variable for struct pixelImage ..

image2

struct pixelimage // create structure to hold image
{
    int **tempa;
    int r,g,b;
    int rows, cols;

}image1,image2;

now read second image and store it in image2, like you have done for image1

combine image1,image2 store result in image1