Question

Language: C++

Course: Computer Programming for Engineers

Write a program that creates two 3x4 arrays of type "int". Populate each array with random integers between 1 and 9. Also ask the user to choose whether they want to add the arrays or subtract the second array from the first array. Output all three arrays in tabular form.

Answer 1

Ans:

#include<cstdlib>//for random numbers generation
#include<iostream>//for basic output and input related operations
using namespace std;
int main(){
   //declaring three 3 X 4 matrices
   //with matrix1,matrix2,matrix3 names respectively
   int matrix1[3][4];
   int matrix2[3][4];
   int matrix3[3][4];
   //integer variables i and j for iteration purpose
   //and option is to choose between addition and subtraction
   int i,j,option;
   //using two nested for loops(because we are working with two dimensional arrays;
   //and filling with random value between 1 to 9(rand() % 9 +1))
   for(i=0;i<3;i++){
       for(j=0;j<4;j++){
           //assigning randome values into the matrices
           matrix1[i][j]=rand() % 9 + 1;
           matrix2[i][j]=rand() % 9 + 1;
       }
   }
   //printing first matrix
   cout<<"\n3 X 4 Matrix1\n";
   for(i=0;i<3;i++){
       for(j=0;j<4;j++){
               cout<<matrix2[i][j]<<"\t";
       }
       cout<<endl;
   }
   //printing second matrix
   cout<<"\n3 X 4 Matrix2\n";
   for(i=0;i<3;i++){
       for(j=0;j<4;j++){
           cout<<matrix2[i][j]<<"\t";
       }
       cout<<endl;
   }
   //small menu with two options
   //asking user to select one operation
   cout<<"----------------------";
   cout<<"\n1.matrix addition ";
   cout<<"\n2.matrix subtraction ";
   cout<<"\nchoose one operation :";
   cin>>option;
   //using switch case statements ,executing only selected case
   switch(option){
   //case 1 is for addition of two matrices 1 and two
   case 1:
       //addition code goes here
       cout<<"Addition of Matrix1 and Matrix2\n";
       for(i=0;i<3;i++){
       for(j=0;j<4;j++){
           cout<<matrix1[i][j]+matrix2[i][j]<<"\t";
       }
           cout<<endl;
       }
       break;
   //case 2 is for subtraction of two matrices
   case 2:
       //
       printf("subtraction of Matrix1 and Matrix2\n");
       for(i=0;i<3;i++){
       for(j=0;j<4;j++){
           cout<<matrix1[i][j]-matrix2[i][j]<<"\t";
       }
       cout<<endl;
       }
       break;      
   }
}

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