Day1: FAQ Interview questions – Coding

This complete series of interviewing questions are divided into days for easy and better understanding. Follow the Day pattern and practice coding as much you can.

1. Find last word count in a sentence: using string and char * using C++.
2. Reverse string using C++,
   1. With temporary variable using C++.
   2. Without temporary variable using C++.
3. Find vowels count in a string using C++.
4. Find a word in a sentence using C++.
5. Find given number is Palindrome using C++.

Find last word count in a sentence : using char * using C++.

#include <iostream>
using namespace std;
int findLenghtlastWord_Char(char *ptrSentence)
{
	if (!ptrSentence)
		return 0;
        int i = strlen(ptrSentence);
        int index = 0;
        int count = 0;

        while (i > 0)
        {
            if (ptrSentence[index] != ' ')
            {
                i--;
                count++;
                index++;
            }
            else
            {
                while (i > 0 && ptrSentence[index] == ' ')
                {
                    i--;
                    index++;

                    if (i != 0)
                        count = 0;
                }

            }
        }
        return count;
  }

Find last word count in a sentence: using string using C++.

int CountLenghtlastWord_String(string sentence)
{
    int i = sentence.length();
    int count = 0;
    int index = 0;

    while (i > 0)
    {
        if (sentence[index] != ' ')
        {
            index++;
            count++;
            i--;
        }
        else
        {
            while (i > 0 && sentence[index] == ' ')
            {
                index++;
                i--;

                if (i != 0)
                    count = 0;
            }
        }
    }

    return count;
}

Reverse string using temporary variable in C++.

char * reverseChar(char *ptrChar)
{
	int len = strlen(ptrChar);
	for (int i = 0, j= len -1;    i<j;  i++, j--)
	{
		char ch = ptrChar[i];
		ptrChar[i] = ptrChar[j];
		ptrChar[j] = ch;
	}
	return ptrChar;
}

Reverse string without using temporary variable in C++.

string reverseWithoutTemp(string strName, int start, int end)
{
	while (start < end)
	{
		strName[start] ^= strName[end];
		strName[end] ^= strName[start];
		strName[start] ^= strName[end];

		++start;
		--end;
	}

	return strName;
}

Find vowels count in a string using C++.

int countVowels(char *sentence)
{
	int len = strlen(sentence);
	int count = 0;
	int index = 0;

	while (len > 0)
	{
		if (toupper(sentence[index]) == 'A' || toupper(sentence[index]) == 'E' ||
			toupper(sentence[index]) == 'I' || toupper(sentence[index]) == 'O' || toupper(sentence[index]) == 'U')
		{
			count++;	
		}	
		len--;
		index++;
	}

	return count;
}

Find a word in a sentence using C++.

bool findWordInSentence(char *sentence, char *key)
{
	int len = strlen(sentence);
	int keylen = strlen(key);
	int count = 0;
	int index = 0;
	int key_index = 0;


	while (len > 0)
	{
		if (sentence[index] == key[key_index])
		{
			count++;
			index++;
			key_index++;
			len--;

			if (keylen == count + 1)
			{
				return true;
			}
		}
		else
		{
			count = 0;
			index++;
			key_index = 0;
			len--;
		}
	}
	return false;
}

Find given number is Palindrome using C++.

bool IsPalindromeString(string key)
{
	int len = key.length();
	int count = 0;

	for (int i = 0, j = len - 1; i < j; i++, j--)
	{
		if (key[i] == key[j])
			count++;
	}

	if (count == len / 2)
		return true;
	else
		return false;

}

Main function for execution:

int main()
{
	char sentence[] = "Hello my name is Mohammed Iliyas Patel ";
	int length1 = findLenghtlastWord_Char(sentence);
	int length2 = CountLenghtlastWord_String(sentence);
	cout << "1. Last word count of string:  '" << sentence << "' = " << length2 << endl;

	char Name[] = "Iliyas";
	reverseChar(Name);
	string revStringName = reverseWithoutTemp(Name, 0, strlen(Name) - 1);
	//reverse(revStringName.begin(), revStringName.end());   std function
	cout << "2. Reverse of '" << Name << "' = "<< revStringName.c_str() << endl;

	int count = countVowels(sentence);
	cout << "3. Vowels in '" << sentence << "' : Count = " << count << endl;

	char Key[] = "Iliyas";
	bool found = findWordInSentence(sentence, Key);
	cout << "4. Word : ' " << Key << " ' : In a sentence '" << sentence << " ' : " << found << endl;

	string Pal = "abddba";
	bool isPalindrome = IsPalindromeString(Pal);
	cout << "5. Given String " << Pal.c_str() << " : Palindrome = " << isPalindrome << endl;
	return 0;
}

OUTPUT:

1. Last word count of string:  ‘Hello my name is Mohammed Iliyas Patel ‘ = 5

2. Reverse of ‘sayilI’ = Iliyas

3. Vowels in ‘Hello my name is Mohammed Iliyas Patel ‘ : Count = 13

4. Word : ‘ Iliyas ‘ : In a sentence ‘Hello my name is Mohammed Iliyas Patel  ‘ : 1

5. Given String abddba : Palindrome = 1