Adding 2 vectors component with component using stack - c++

Question

I have a problem with my C++ code. I need to make the sum of the vectors component by component. For example, if I have A(2,1) and B(3,3) the result should be (5,4). I tried to do something but apparently I have a problem and I don't know what to do. The error is: ,,No member called push in std::_1vector" My code is:
#include <iostream>
#include "stack_base.h"
#include <vector>
using namespace std;
template<typename T>
class App {
public:
Stack<T> * stack;
App(Stack<T> &stack) {
this->stack = &stack;
}
T sum(){
Stack<T> *tempStack = stack;
T sum=0;
int size = stack->getTopLevel();
for(int i=0; i<=size; i++) {
sum+=tempStack->peek();
tempStack->pop();
}
return sum;
}
T substract(){
Stack<T> tempStack = *stack;
T substr=0;
for(int i=0; i<=stack->getTopLevel(); i++) {
substr-=tempStack.peek();
tempStack.pop();
}
return substr;
}
};
void display(vector<int> &v)
{
for(int i = 0; i < v.size(); i++)
{
cout << v[i] << " ";
}
cout << "\n" << endl;
}
int main(){
using namespace std;
Stack<int> myStack;
App<int> a(myStack);
unsigned int i = 0;
std::vector<int> v1;
std::vector<int> v2;
// Populate v1 and v2 here
// Check that v1 and v2 have the same length
if (v1.size() != v2.size())
{
// error here
}
std::vector<int> v3; // This will hold the resulting vector
// Preallocate the necessary memory if you like here, but it
// isn't necessary and doesn't gain you much.
for (auto i = 0ul; i < v1.size(); ++i)
{
v3.push_back(v1[i] + v2[i]);
}
int x;
cout << "Enter five integer values for v1" << endl;
for(int i; i<5; i++)
{
cin >> x;
v1.push_back(x);
}
cout << "Enter five integer values for v2" << endl;
for(int i; i<5; i++)
{
cin >> x;
v2.push_back(x);
}
cout << "Size of Vector= " << v2.size() << endl;
display(v3);
return 0;
}
This is Stack:
#include <iostream>
using namespace std;
#define NMAX 30 // pre-processing directive
template<typename T>
class Stack {
private:
// an array of NMAX dimension
T stackArray[NMAX];
/* the top of the stack, representing the INDEX of last element of the
stackArray:0, 1, 2,....*/
int topLevel;
public:
void push(T x) {
//puts an element in the stack array
//check if the stack array has the maximum dimension
if (topLevel >= NMAX - 1)
{
cout<<"The stack is full: we have already NMAX elements!\n";
//exit the function without making anything
return;
}
/*add an element=> the index of the last element of the stack Array
increases and put the value of the new element in the stack array*/
stackArray[++topLevel] = x;
}
int isEmpty() {
//returns 1, if topLevel>=0, meaning the stack array has elements
// returns 0, otherwise
return (topLevel < 0);
}
T pop() {
// extracts and element from the stack array and returns the new top
if (isEmpty()) {
// the extraction is made only if the array is not empty
cout<<"The stack is empty! \n";
T x;
return x;
}
// the topLevel decreases and the new top is changed
return stackArray[--topLevel];
}
T peek() {
// returns the top of the stack
if (isEmpty()) {
// the extraction is made only if the array is not empty
cout<<"The stack is empty! \n";
T x;
return x;
}
return stackArray[topLevel];
}
void display(){
for(int i=0;i<=topLevel;i++)
cout<<stackArray[i];
}
bool search(T num){
for(int i=0; i<=topLevel;i++)
if(num==stackArray[i])
return true;
return false;
}
int getTopLevel(){
return topLevel;
}
Stack() { // constructor
topLevel = -1; // the stack is empty in the beginning
}
void sort(T s){
if (!isEmpty()) {
T x = Pop(s);
sort(s);
push(s, x);
}
}
~Stack() { // destructor
}
};

Answer 1

You are never adding any elements to your vector. In the preceding three lines, you attempt to access elements that do not exist, but the vectors only do bounds checking if you call the 'at' method instead of using the bracket notation. What are you trying to accomplish in that for-loop?
To add two vectors of the same length pair-wise, which is what I think you want, you can do this:
std::vector<int> v1;
std::vector<int> v2;
// Populate v1 and v2 here
// Check that v1 and v2 have the same length
if (v1.size() != v2.size())
{
// error here
}
std::vector<int> v3; // This will hold the resulting vector
// Preallocate the necessary memory if you like here, but it
// isn't necessary and doesn't gain you much.
for (auto i = 0ul; i < v1.size(); ++i)
{
v3.push_back(v1[i] + v2[i]);
// Debugging statement
std::cout << "Added " << v1[i] << " and " << v2[i] << " to get " << v3[i] << " for index " << i << std::endl;
}