Question

1. Given a string, write a method called removeRepthat returns another string where adjacent characters that are the same have been reduced to a single character. Test the program by calling the method from the main method. For example:

removeRep(“yyzzza”) à “yza”

removeRep(“aabbbccd”) à “abcd”

removeRep(“122333”) à “123”

Answer 1

Here is the complete code filled with comments to help understand all the lines.

The code is in c++ but can also be applied to java and other languages as the logic remains the same.

//These are the required header file
#include <iostream>
#include <string>
using namespace std;

string removeRep(string str)
{
    //first we take the length of the string
    int len = str.size();
    //if length is less 2 we can simple return the string as it is
    if (len <= 1)
        return str;
    int j = 0;
    //we have kept the variable j to increase ONLY when we find a new unique element, thus there are no duplicates
    for (int i = 1; i < len; i++)
    {
        if (str[i] != str[j])
        {
            str[++j] = str[i];
        }
    }
    j++;
    //at last resize the string to the required length ie j
    str.resize(j);
    return str;
}

int main()
{
    cout << removeRep("aazzzpp") << "\n";
    cout << removeRep("aabbbccccddd") << "\n";
    cout << removeRep("abcd") << "\n";
    cout << removeRep("bppppaz") << "\n";
    return 0;
}

Here is the output for the above code