header

Loops and Collections

If we want to change the value of the character in a string, we must define the loop variable as a reference type.

#include <iostream>
using namespace std;

int main(){
  string nickname = "josdem";

  for(char &c: nickname){
    c = toupper(c);
  }

  cout << nickname << endl;
}

Vector

A vector is a collection of objects, all which have the same type. Every object in the collection has an associated index, which gives access to that object. To use a vector, we must include the header.

#include <iostream>
#include <vector>

using namespace std;

int main(){
  vector<int> integers = {1,2,3,4,5};

  for(int i=6; i < 10; i++){
    integers.push_back(i);
  }

  for(int i: integers){
    cout << i << endl;
  }

}

Vector operations

  • vector.empty();
  • vector.size();
  • vector.push_back(t)
  • vector[n];

Arrays

An array is a data structure that is similar to the vector, but it has a fixed size; so it offer a better run time performance.

#include <iostream>

using namespace std;

int main(){
  int integers[10] = {0,1,2,3,4};

  for(int i=5; i < 10; i++){
    integers[i] = i;
  }

  for(int i: integers){
    cout << i << endl;
  }

}

WARNING We cannot initialize an array as a copy of anorher array.

You can define multidimensional arrays int matrix[3][4] this is an array of size 3; each element is an array of ints of size 4

Return to the main article

With your donation, you help me to maintain this site and posts.





comments powered by Disqus