Spaghetti
Time Limit: 1 Second Memory Limit: 32768 KB
Early languages like Fortran IV use conditional and unconditional goto statements instead of structured statements like if and while. In Fortran IV, each statement occupies a line of input. The first five positions in each line are reserved for an optional label, which is an integer. The next position is reserved for a continuation marker, which we shall not consider further. Therefore, statements occupy positions 7 and beyond in each input line. The goto statement looks like thisgoto label
and the conditional goto statement looks like this
if(expression)goto label
The language contains many other statements, but only the conditional goto
begins with "if(" and ends with ")goto label" where label
is an integer. All spaces are ignored within a Fortran IV statement. For this
problem, the "stop" statement, which halts execution, appears only
as the last line of the program.
Your job is to determine whether or not two Fortran programs are equivalent.
They are equivalent if, for all possible inputs, they execute exactly the same
sequence of statements, ignoring unconditional gotos and labels. By "the
same sequence of statements" we mean statements that are textually identical,
after spaces and labels are removed. You must assume that each conditional goto
will be taken for some inputs and not taken for others. Unconditional gotos
are, of course, always taken. The two programs in the sample input are equivalent.
Input
Your input consists of pair ofprograms separated by a blank line. No input line exceeds 80 characters and no program contains more than 1000 lines. Each label used in a goto statement appears to the left of exactly one statment; no label is repeated. Subsequent test cases are separated with a single blank line.
Output
Output for each test consists if a single line, stating either "The programs are equivalent." or "The programs are not equivalent."
Sample Input
read 6, i,k,j 99 if(i .lt. j)goto 33 goto 55 33 i=j goto 99 55 k=j+1 stop read6,i,k,j if(i.lt.j)goto12345 77 k=j+1 goto5555 12345 i=j if(i.lt.j)goto12345 goto77 88 goto88 5555 stop
Sample Output
The programs are equivalent.Submit
Source: University of Waterloo Local Contest 1999.01.31