C++ program that counts the occurrences of each character in a given string

 

Here's a C++ program that counts the occurrences of each character in a given string:

cpp
#include <iostream>
#include <map>

int main() {
    std::string inputString;
    std::cout << "Enter a string: ";
    std::getline(std::cin, inputString);

    std::map<char, int> characterCount;

    for (char character : inputString) {
        // Ignore whitespace characters
        if (!std::isspace(character)) {
            characterCount[character]++;
        }
    }

    std::cout << "Character occurrences:" << std::endl;
    for (const auto& entry : characterCount) {
        std::cout << "'" << entry.first << "': " << entry.second << " times" << std::endl;
    }

    return 0;
}

Explanation:

1. 1. The program uses a std::map named characterCount to store the counts of each character in the input string.
2. 2. The program first takes an input string from the user using std::getline, which allows for reading a complete line of text.
3. 3. The program then iterates through each character in the input string.
4. 4. Inside the loop, whitespace characters (like spaces or tabs) are ignored using the std::isspace function.
5. 5. The non-whitespace characters are inserted into the characterCount map, and their counts are incremented.
6. 6. After processing all characters, the program prints out the occurrences of each character.
7. 7. The for loop iterates through the characterCount map and prints the character and its corresponding count.

For example, if the user inputs "hello world", the output might be:

cpp
Enter a string: hello world
Character occurrences:
'h': 1 times
'e': 1 times
'l': 3 times
'o': 2 times
'w': 1 times
'r': 1 times
'd': 1 times

In this example, the program counts and displays the occurrences of each character in the input string, while ignoring whitespace characters.

C++ program that counts the occurrences of each digit in a given number

 

A C++ program that counts the occurrences of each digit in a given number:

cpp
#include <iostream>
#include <map>

int main() {
    long long number;
    std::cout << "Enter a number: ";
    std::cin >> number;

    std::map<int, int> digitCount;

    while (number > 0) {
        int digit = number % 10;
        digitCount[digit]++;
        number /= 10;
    }

    std::cout << "Digit occurrences:" << std::endl;
    for (const auto& entry : digitCount) {
        std::cout << "Digit " << entry.first << ": " << entry.second << " times" << std::endl;
    }

    return 0;
}

Explanation:

1. The program uses a std::map named digitCount to store the counts of each digit in the input number.
2. The program takes an input number from the user.
3. The program then enters a loop where it repeatedly extracts the last digit of the number using the modulo operator % and divides the number by 10 to remove the last digit.
4. The extracted digit is inserted into the digitCount map, and its count is incremented.
5. The loop continues until the number becomes zero.
6. After processing all digits, the program prints out the occurrences of each digit.
7. The for loop iterates through the digitCount map and prints the digit and its corresponding count.

For example, if the user inputs 12233442, the output might be:

cpp
Enter a number: 12233442
Digit occurrences:
Digit 1: 2 times
Digit 2: 4 times
Digit 3: 2 times
Digit 4: 2 times

In this example, the program counts and displays the occurrences of each digit in the input number.