Finding Records Using awk Command using math score - unix

Question

Write the unix command to display all the fields of students who has score more than 80 in math as well as math score should be top score among all subjects, moreover output should be in ascending order of std(standard)of the students.
INPUT:
roll,name,std,science_marks,math_marks,college
1,A,9,60,86,SM
2,B,10,85,80,DAV
3,C,10,95,92,DAV
4,D,9,75,92,DAV
OUTPUT:
1|A|9|60|86|SM
4|D|9|75|92|DAV
myCode:
awk 'BEGIN{FS=',' ; OFS="|"} {if($4<$5 && $5>80){print $1,$2,$3,$4,$5,$6}}'
but I'm getting unexpected token error please help me.
Error Message on my Mac System Terminal:
awk: syntax error at source line 1
context is
BEGIN >>> {FS=, <<<
awk: illegal statement at source line 1

Answer 1

Could you please try following, written and tested with shown samples in GNU awk. This answer doesn't hard code the field number it gathers column which has math in it and checks for rest of the lines accordingly then.
awk '
BEGIN{
FS=","
OFS="|"
}
FNR==1{
for(i=1;i<=NF;i++){
if($i=="math_marks"){ field=i }
}
next
}
{
for(i=3;i<=(NF-1);i++){
max=(max>$i?(max?max:$i):$i)
}
if(max==$field && $field>80){ $1=$1; print }
max=""
}
' Input_file
Explanation: Adding detailed explanation for above.
awk ' ##Starting awk program from here.
BEGIN{ ##Starting BEGIN section of code here.
FS="," ##Setting field separator as comma here.
OFS="|" ##Setting output field separator as | here for all lines.
}
FNR==1{ ##Checking condition if its first line then do following.
for(i=1;i<=NF;i++){ ##Going through all fields here.
if($i=="math_marks"){ field=i } ##Checking if a field value is math_marks then set field to tht field numner here.
}
next ##next will skip all further statements from here.
}
{
for(i=3;i<=(NF-1);i++){ ##Going through from 3rd field to 2nd last field here.
max=(max>$i?(max?max:$i):$i) ##Creating max variable which checks its value with current field and sets maximum value by comparison here.
}
if(max==$field && $field>80){ $1=$1; print } ##After processing of all fields checking if maximum and field value is equal AND math number field is greater than 80 then print the line.
max="" ##Nullifying max var here.
}
' Input_file ##Mentioning Input_file name here.

Answer 2

Your code has double quotes of wrong encoding:
here
| |
v v
$ busybox awk 'BEGIN{FS=”,” ; OFS="|"} {if($4<$5 && $5>80){print $1,$2,$3,$4,$5,$6}}'
awk: cmd. line:1: Unexpected token
Replace those and your code works fine.