NRUOST 

Given below are some letters, with the codes used for these written below Conditions: (i) If the first letter is a consonant and the second last letter is a vowel, then both are to be coded as the code of the vowel. (ii) If both the first letter and the last letter are vowels, then both these letters are to be coded as ‘z’. (iii) If only one vowel is present in the group of letters, then third and the fifth letters’ codes are to be interchanged. (iv) If both the first and the last letters are consonants, then their codes would be the codes of their next letters in the English Alphabets.