[CentOS] Semi-OT: awk

This is odd, and annoying. CentOS 6, current. Here's my awk script:

{ room = substr($0, 48, 10); arr[$2,room,$1] = $0; } END { for ( i in arr ) { for ( j in arr[i] ) { for ( k in arr[i][j] ) { print arr[i][j][k]; } } } }

And when I run it, it complains awk -f awksort proplist7 awk: awksort:7: for ( j in arr[i] ) { awk: awksort:7: ^ syntax error awk: awksort:8: for ( k in arr[i,j] ) { awk: awksort:8: ^ syntax error awk: awksort:9: print arr[i][j][k]; awk: awksort:9: ^ syntax error

which makes no sense - I've done this a million times. Am I missing something, or is this a bug?

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