co [ i ] is going to store counts of consonants from str [ len - 1 ] to str [ i ] . vo [ i ] is going to store counts of vowels from str [ len - 1 ] to str [ i ] .
int co [ len + 1 ] ; int vo [ len + 1 ] ; memset ( co , 0 , sizeof ( co ) ) ; memset ( vo , 0 , sizeof ( vo ) ) ;