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COBOL SEARCH स्टेटमेंट दो रूपों में आता है। रैखिक ऊपर से नीचे तक SEARCH और एक द्विआधारी SEARCH ALL एल्गोरिथ्म। बाइनरी खोज सभी एक क्रमबद्ध तालिका को मानते हैं जो बाइनरी खोज के लिए उपयुक्त है, जिसमें कोई भी ऑर्डर नहीं है।
खोज बयान
रैखिक खोज
बाइनरी खोज सभी
रेखीय खोज
GCobol >>SOURCE FORMAT IS FIXED
*> ***************************************************************
*> Purpose: Demonstration of the SEARCH verb
*> Tectonics: cobc -x searchlinear.cob
*> ***************************************************************
identification division.
program-id. searchlinear.
data division.
working-storage section.
01 taxinfo.
05 tax-table occurs 4 times indexed by tt-index.
10 province pic x(2).
10 taxrate pic 999v9999.
10 federal pic 999v9999.
01 prov pic x(2).
01 percent pic 999v9999.
01 percentage pic zz9.99.
*> ***************************************************************
procedure division.
begin.
*> ***************************************************************
*> Sample for linear SEARCH, requires INDEXED BY table
*> populate the provincial tax table;
*> *** (not really, only a couple of sample provinces) ***
*> populate Ontario and PEI using different field loaders
move 'AB' to province(1)
move 'ON' to province(2)
move 0.08 to taxrate(2)
move 0.05 to federal(2)
move 'PE00014000000000' to tax-table(3)
move 'YT' to province(4)
*> Find Ontario tax rate
move "ON" to prov
perform search-for-taxrate
*> Setup for Prince Edward Island
move 'PE' to prov
perform search-for-taxrate
*> Setup for failure
move 'ZZ' to prov
perform search-for-taxrate
goback.
*> ***************************************************************
search-for-taxrate.
set tt-index to 1
search tax-table
at end display "no province: " prov end-display
when province(tt-index) = prov
perform display-taxrate
end-search
.
display-taxrate.
compute percent = taxrate(tt-index) * 100
move percent to percentage
display
"found: " prov " at " taxrate(tt-index)
"," percentage "%, federal rate of " federal(tt-index)
end-display
.
end program searchlinear.
बाइनरी खोज सभी
GCobol >>SOURCE FORMAT IS FIXED
*> ***************************************************************
*> Purpose: Demonstration of the SEARCH ALL verb and table SORT
*> Tectonics: cobc -x -fdebugging-line searchbinary.cob
*> ***************************************************************
identification division.
program-id. searchbinary.
environment division.
input-output section.
file-control.
select optional wordfile
assign to infile
organization is line sequential.
data division.
file section.
fd wordfile.
01 wordrec pic x(20).
working-storage section.
01 infile pic x(256) value spaces.
88 defaultfile value '/usr/share/dict/words'.
01 arguments pic x(256).
*> Note the based clause, this memory is initially unallocated
78 maxwords value 500000.
01 wordlist based.
05 word-table occurs maxwords times
depending on wordcount
descending key is wordstr
indexed by wl-index.
10 wordstr pic x(20).
10 wordline usage binary-long.
01 wordcount usage binary-long.
01 file-eof pic 9 value low-value.
88 at-eof value high-values.
01 word pic x(20).
*> ***************************************************************
procedure division.
begin.
*> Get the word file filename
accept arguments from command-line end-accept
if arguments not equal spaces
move arguments to infile
else
set defaultfile to true
end-if
*> ***************************************************************
*> Try playing with the words file and binary SEARCH ALL
*> requires KEY IS and INDEXED BY table description
*> Point wordlist to valid memory
allocate wordlist initialized
open input wordfile
move low-value to file-eof
read wordfile
at end set at-eof to true
end-read
perform
with test before
until at-eof or (wordcount >= maxwords)
add 1 to wordcount
move wordrec to wordstr(wordcount)
move wordcount to wordline(wordcount)
read wordfile
at end set at-eof to true
end-read
end-perform
close wordfile
*> ensure a non-zero length table when allowing optional file
evaluate true also file-eof
when wordcount = 0 also any
move 1 to wordcount
display "No words loaded" end-display
when wordcount >= maxwords also low-value
display "Word list truncated to " maxwords end-display
end-evaluate
>>D display "Count: " wordcount ": " wordstr(wordcount) end-display
*> Sort the words from z to a
sort word-table on descending key wordstr
*> fetch a word to search for
display "word to find: " with no advancing end-display
accept word end-accept
*> binary search the words for word typed in and display
*> the original line number if/when a match is found
set wl-index to 1
search all word-table
at end
display
word " not a word of " function trim(infile)
end-display
when wordstr(wl-index) = word
display
word " sorted to " wl-index ", originally "
wordline(wl-index) " of " function trim(infile)
end-display
end-search
*> Release memory ownership
free address of wordlist
goback.
end program searchbinary.
Modified text is an extract of the original Stack Overflow Documentation
के तहत लाइसेंस प्राप्त है CC BY-SA 3.0
से संबद्ध नहीं है Stack Overflow