Question

C++

C. In the file c_final_practice.cpp: (1) Write a function void replace(vector<int>& v, int old, int new) that replaces all occurrences of the integer old in v with the integer new. For example, if v is the vector {1,2,1,3}, then after calling replace(v, 1, 3) v should be {3,2,3,3}. (2) Write the main-function so that it prompts the user for a list of integers, and then uses your replace function to display the following lists: • The user's list with all O's replaced by 2’s. • The user's list with all O's replaced by l’s, and all l's replaced by O's. You must use your replace function to get full credit on this part. Example Enter a list of integers. Type Q to quit. 0 1 2 -1 0 -2 1 Q 2 1 2 -1 2 -2 1 1 0 2 -1 1 -2 0

Answer 1

#include<iostream>
#include <vector>
using namespace std;
// replace the old value with new
void replace(vector<int>& v,int old,int neww)
{
    // iterate the vector
    for(int i=0;i<v.size();i++)
    {
        if(v[i] == old)
            v[i] = neww; // replace the all occurences of old value with new value
    }
}
int main()
{
    //main program start here
    vector<int>v;
    // initialize three vector
    vector<int>v1;
    vector<int>v2;
    vector<int>v3;
    string input; // declare input as string
    cout<<"Enter a list of integers. Type Q to quit."<<endl;
    while(true)
    {
        cin>>input; //take input from user
        if(input == "Q") // if the input is Q then stop taking input
            break;
        v.push_back(atoi(input.c_str())); // Converting string to integer
    }
      
    // take the copy of v in v1,v2,v3
    v1 = v;
    v2 = v;
    v3 = v;
    replace(v1,0,2); // call replace function for replace 0 by 2
    for (int i = 0; i < v1.size(); i++) // display the list of integers after replace
        cout<<v1[i]<<" ";
    cout<<endl;

    replace(v2,0,1); // call replace function for replace 0 by 1
    for (int i = 0; i < v2.size(); i++) // display the list of integers after replace
        cout<<v2[i]<<" ";
    cout<<endl;

   replace(v3,1,0); // call replace function for replace 1 by 0
    for (int i = 0; i < v3.size(); i++) // display the list of integers after replace
        cout<<v3[i]<<" ";
    cout<<endl;

  
}

**********************OUTPUT*****************************
Enter a list of integers. Type Q to quit.
0 1 2 -1 0 -2 1 Q
2 1 2 -1 2 -2 1
1 1 2 -1 1 -2 1
0 0 2 -1 0 -2 0