How to Change Cases of Letters of a String in C++

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How to Change Cases of Letters of a String in C++:

In this article, I am going to discuss How to Change Cases of Letters of a String in C++ Language with examples. Please read our previous article, where we discussed How to Find the Length of a String in C++ with examples.

How to Change Cases of Letters of a String in C++?

Here, we will write a program that will change the cases of letters of the given string. Let us see the program.

Program 1: Upper case to Lower case.

#include <iostream>
#include <string.h>
using namespace std;
int main()
{
    string str = "BISCUITS";
    for (int i = 0; str[i] != '\0'; i++)
    {
        if (str[i] >= 65 && str[i] <= 90)
        {
            str[i] = str[i] + 32;
        }
    }
    cout << str << endl;
    return 0;
}

Output:

Program 2: Lower case to Upper case.

#include <iostream>
#include <string.h>
using namespace std;
int main()
{
    string str = "breakfast";
    for (int i = 0; str[i] != '\0'; i++)
    {
        if (str[i] >= 97 && str[i] <= 122)
        {
            str[i] = str[i] - 32;
        }
    }
    cout << str << endl;
    return 0;
}

Output:

In the next article, I am going to discuss How to Count Vowels, Consonants, and Words in a String in C++ with examples. Here, in this article, I try to explain How to Change Cases of Letters of a String in C++ Language with examples. I hope you enjoy this How to Change Cases of Letters of a String in C++ with examples article. I would like to have your feedback. Please post your feedback, question, or comments about this article.