One line if statement in bash

Question

I've never programed in bash... yet I'm trying to solve a problem for an anchievement in a game (codingame.com)

I have the following code:

for (( i=0; i<N-1; i++ )); do
   tmp=$(( sorted_array[i+1] - sorted_array[i] ));
   if [ $tmp < $result ]; then result=$tmp fi
done

And this error:

/tmp/Answer.sh: line 42: syntax error near unexpected token `done'at Answer.sh. on line 42
/tmp/Answer.sh: line 42: `done' at Answer.sh. on line 42

I want to compare adjacent values of my array and store the minimun diference between them... but I cant figure how to do an If statement in bash

Answer 1

Each command must be properly terminated, either by a newline or a semi-colon. In this case, you need to separate the assignment of result from the keyword fi. Try adding a semi-colon;

for (( i=0; i<N-1; i++ )); do
   tmp=$(( sorted_array[i+1] - sorted_array[i] ))
   if [ "$tmp" -lt "$result" ]; then result=$tmp; fi
done

Also, you need to use lt rather than <, since < is a redirection operator. (Unless you intend to run a command named $tmp with input from a file named by the variable $result)

Answer 2

You are missing a semicolon and need to use -lt instead of <, as others pointed out.

An alternative to the if statement would be to use the logical and operator &&:

for (( i=0; i<N-1; i++ )); do
   tmp=$(( sorted_array[i+1] - sorted_array[i] ))
   [ $tmp -lt $result ] && result=$tmp
done