You have ‘n’ number of balls of 3 different colours and all are mixed up. Write an algorithm to group the balls of the same colour.(eg.i/p:RBWRBWR o/p:RRRBBWW)
Let ball[1 to n] be the array which contains the color of the n balls which can be either R or B or W.
FNR is the index of the first non red ball and LNW is the index of the last non white ball. i will be a traversing pointer which will move from index next to FNR until it reaches next to LNW.
Step 1: set FNR=1
do until ball[FNR]!=R
{
FNR=FNR+1
}
Step 2: set LNW=n
do until ball[LNW]!=W
{
LNW=LNW-1;
}
Step 3: set i=FNR
do until i>LNW
{
if ball[i]=R
{
swap ball[i] and ball[FNR]
increment FNR
}
else if ball[i]=W
{
swap ball[i] and ball[LNW]
decrement LNW
}
increment i
}
