C++ Programs and Wild

Wildcards in C++ are special characters that can be used to represent any other character or group of characters. This makes it easier to search for and manipulate text in strings or files.

Syntax

Wildcards are represented by special characters that have a special meaning. Some commonly used wildcards include:

• ? - matches any single character
• * - matches any sequence of characters (including none)
• [] - matches any character within the specified range or set
• [^] - matches any character that is not within the specified range or set

string wildcard_pattern = "pattern*";
string input_string = "pattern_matching_example";

if (wildcard_match(wildcard_pattern, input_string)) {
    cout << "Match found!" << endl;
} else {
    cout << "No match found." << endl;
}

Example

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

bool wildcard_match(string pattern, string input) {
    int i = 0, j = 0;
    while (i < pattern.size() && j < input.size()) {
        if (pattern[i] == '?') {
            i++;
            j++;
        } else if (pattern[i] == '*') {
            if (i == pattern.size() - 1) {
                return true;
            }
            while (input[j] != pattern[i+1] && j < input.size()) {
                j++;
            }
            i++;
        } else ifpattern[i] == input[j]) {
            i++;
            j++;
        } else {
            return false;
        }
    }
    if (i < pattern.size() - 1) {
        return false;
    else if (j < input.size()) {
        return false;
    }
    return true;
}

int main() {
    string pattern = "p*tte?n";
    string input1 = "pattern";
    string input2 = "potterton";
    string input3 = "patteern";
    if (wildcard_match(pattern, input1)) {
        cout << "Match found for input1." << endl;
    }
    if (wildcard_match(pattern, input2)) {
        cout << "Match found for input2." << endl;
    }
    if (wildcard_match(pattern, input3)) {
        cout << "Match found for input3." << endl;
    }
    return 0;
}

Output

Match found for input1.
Match found for input2.
No match found.

Explanation

In the above example, we have implemented a function to perform a wildcard match between a pattern and an input string. We have used the ? and * wildcards to match any single character or sequence of characters. We then test our function with three different input strings to verify that it works correctly.

Use

Wildcards are commonly used in applications such as file search and string manipulation. They allow you to search for patterns in large datasets or identify matches based on a certain criteria.

Important Points

• Wildcards represent special characters that match any other character or group of characters.
• Common wildcards include ?, *, [], and [^].
• Wildcards are useful in applications such as file search and string manipulation.

Summary

In summary, wildcards in C++ are a powerful tool for pattern matching and string manipulation. They allow you to search for and manipulate text based on a certain criteria, making it easier to work with large datasets and complex applications.