Operations on Strings in C++

Understanding Operations on Strings

String operations involve various manipulations such as concatenation, reversal, and comparison.

We will explore three different methods to perform operations on strings in C++.

Method 1: Using Standard Library Functions

This method uses built-in string functions for operations.

#include <iostream>
#include <algorithm>
#include <string>
using namespace std;

int main() {
    string str1 = "Hello";
    string str2 = " World";
    str1 += str2;
    cout << "Concatenated String: " << str1 << endl;
    cout << "Length of String: " << str1.length() << endl;
    return 0;
}
            

Method 2: Using Character Array Manipulation

This method manually processes each character for operations.

#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;

void reverseString(char str[]) {
    int length = strlen(str);
    for (int i = 0; i < length / 2; i++) {
        swap(str[i], str[length - i - 1]);
    }
}

int main() {
    char str[] = "Hello";
    reverseString(str);
    cout << "Reversed String: " << str << endl;
    return 0;
}
            

Method 3: Using Pointer Manipulation

This method performs operations using pointers.

#include <iostream>
#include <algorithm>
using namespace std;

int compareStrings(const char *str1, const char *str2) {
    while (*str1 && *str2 && *str1 == *str2) {
        str1++;
        str2++;
    }
    return *str1 - *str2;
}

int main() {
    const char str1[] = "Hello";
    const char str2[] = "Hello";
    int result = compareStrings(str1, str2);
    if (result == 0)
        cout << "Strings are equal" << endl;
    else
        cout << "Strings are not equal" << endl;
    return 0;
}