Question

Write a function num_dups that takes in a string and returns the number of duplicated characters in the string.

Hint: You can use a std::map to maintain a count of the characters.

#include <string>

using namespace std;

int num_dups(string str) {
//code

}

Answer 1

Answer provided by AssignmentExpert.com

Assignment:

Write a function num_dups that takes in a string and returns the number of duplicated characters in the string.

Hint: You can use a std::map to maintain a count of the characters.

#include<string>
using namespace std;
int num_dups(string str) { //code }

Solution:

I've made two versions of this solution. First one implies that input "Hello" provides the result equals "1" (it means that letter "I" duplicates only once):

int num_dups(string str) {
    string copy_str = str;
    int num_of_dups = 0;
    for (int symbol = 0; copy_str[symbol] != '\0'; symbol++)
    {
        for (int comp_symbol = symbol + 1; copy_str[comp_symbol] != '\0'; comp_symbol++)
        {
            if (copy_str[symbol] == copy_str[comp_symbol] && (copy_str[comp_symbol] >= 'A' && copy_str[comp_symbol] <= 'Z') || (copy_str[comp_symbol] >= 'a' && copy_str[comp_symbol] <= 'z'))
            {
                bool rep = true;
                num_of_dups++;
                copy_str[comp_symbol] = '#';
            }
        }
    }
    return num_of_dups;
}

The second one implies that input "Hello" provides the result equals "2" (it means that letter "I" duplicates only once, but function also counts the first entry of this letter):

int num_dups(string str) {
    string copy_str = str;
    int num_of_dups = 0;
    for (int symbol = 0; copy_str[symbol] != '\0'; symbol++)
    {
        bool rep = false;
        for (int comp_symbol = symbol + 1; copy_str[comp_symbol] != '\0'; comp_symbol++)
        {
            if (copy_str[symbol] == copy_str[comp_symbol] && (copy_str[comp_symbol] >= 'A' && copy_str[comp_symbol] <= 'Z') || (copy_str[comp_symbol] >= 'a' && copy_str[comp_symbol] <= 'z'))
            {
                rep = true;
                num_of_dups++;
                copy_str[comp_symbol] = '#';
            }
        }
        if (rep)
        {
            num_of_dups++;
        }
    }
    return num_of_dups;
}