This is an exception analyzer for one of the coding championship problems.
Imagine a language with this syntax:
-
func f() {...}— function declaration -
maybethrow exc1— instruction where exception can be thrown -
try {...} suppress exc1— try block with types of suppressed exceptions in it -
f()— function call
All instructions, except function declarations, can be located in the body of a function only. Functions cannot be declared inside other functions. The function can be called before its declaration, as well as in its own body.
The names of functions and exceptions in the language must match the regular expression [a-zA-Z0-9_]+, be unique and not match the keywords [func,try,suppress,maybethrow].
The text of a program can contain an arbitrary number of spaces and blank lines.
The first line of input contains a single integer — the number of function declarations in the code.
It is guaranteed that the program contains the declaration of the main function.
The analyzer gets the text of a program and prints exceptions thrown from main function.
The first line of the output must contain the number of exceptions that the main function can throw. In subsequent lines, the names of these exceptions should be printed one by one.
Input:
2
func func1() {
maybethrow exc1
try {
maybethrow exc2
maybethrow exc3
} suppress exc1, exc2, exc3
maybethrow exc4
}
func main() {
try {
func1()
} suppress exc1
}
Output:
1
exc4
Input:
6
func func1(){maybethrow exc1 func1()}
func func2( ) {
func3 ()
}
func func3 ( ) {
func2 ( )
maybethrow exc3
}
func func4( ) {
func3 ()
try {
maybethrow exc4
func5 ()
} suppress exc3
}
func func5( ) {
maybethrow exc4
maybethrow exc3
try {
maybethrow exc5
} suppress exc3
}
func main ( ) {
func1( )
func2( )
func3( )
func4 ()
try {
maybethrow exc2
maybethrow exc3
maybethrow exc4
try{maybethrow exc6 maybethrow exc7 maybethrow exc8}suppress exc8
maybethrow exc5
} suppress exc3 , exc5
}
Output:
7
exc7
exc6
exc5
exc4
exc3
exc2
exc1