$ java parser3
Enter an arithmetic expression
adU + ( ty2 + Hk1 ) / ertiA _ w
invalid expression
error1 invalid id or unknown operator
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n
Enter an arithmetic expression
adU + ( rtyr^ )
invalid expression
error1 invalid id or unknown operator
error3 ) entered without ( in front
error4 ( entered without )
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Enter a q to quit, enter any other key to continue.
n
Enter an arithmetic expression
freU7 * ( mbtrj% )
invalid expression
error1 invalid id or unknown operator
error3 ) entered without ( in front
error4 ( entered without )
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Enter a q to quit, enter any other key to continue.
greY + ( er2 - Fre3 ) / ( ertg * rt )
Enter an arithmetic expression
greY + ( er2 - Fre3 ) / ( ertg * rt )
valid expression
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no
Enter an arithmetic expression
( ert )
valid expression
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no
Enter an arithmetic expression
( ( ( U ) 0
 invalid expression
error1 invalid id or unknown operator
error4 ( entered without )
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n
Enter an arithmetic expression
( ( U ) )
valid expression
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( ( U + V ) * ( T + I ) )
Enter an arithmetic expression
*
invalid expression
error3 ) entered without ( in front
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n
Enter an arithmetic expression
( ( U + V ) * ( H + O ) )
valid expression
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v
Enter an arithmetic expression
( T * y )
valid expression
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no
Enter an arithmetic expression
Er + ( TY * ( yu ) )
valid expression
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( Gh + (Y-( (
Enter an arithmetic expression
( Gh + ( U / Gt5 ) ) * ty
valid expression
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( ( T + G ) ? o )
Enter an arithmetic expression
(( ( I + P )
invalid expression
error1 invalid id or unknown operator
error3 ) entered without ( in front
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no
Enter an arithmetic expression
( ( Y _ U)
invalid expression
error1 invalid id or unknown operator
error4 ( entered without )
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h
Enter an arithmetic expression
*u
invalid expression
error1 invalid id or unknown operator
error3 ) entered without ( in front
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n
Enter an arithmetic expression
( ( Th - th ) / f% )
invalid expression
error1 invalid id or unknown operator
error3 ) entered without ( in front
error4 ( entered without )
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n
Enter an arithmetic expression
adf % dtry
invalid expression
error1 invalid id or unknown operator
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n
Enter an arithmetic expression
Tuty & ou
invalid expression
error1 invalid id or unknown operator
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Enter a q to quit, enter any other key to continue.
q
$