The following shell scripting program is written in bash to calculate combination formula which is n! /(n-r)!r!.
Code:
#!/bin/bash clear echo "Program to find Combination in Probability" function fact { mul=1 i=$1 while [[ $i -gt 1 ]] do sub=`expr $i - 1` mul=`expr $mul \* $i` i=$sub done echo $mul } echo "Enter value for n" n= read n a=`fact $n` echo "Enter Value for r" r= read r b=`fact $r` c=`expr "$n" - "$r"` d=`fact $c` t=`expr "$b" \* "$d"` ans=`expr "$a" / "$t"` echo "Answer For $n! / ($n - $r)!($r)! is" echo "$ans"
OUTPUT: