http://www.jexp.ru/index.php?action=history&feed=atom&title=Java_Tutorial%2FClass_Definition%2FRecursive_Method
Java Tutorial/Class Definition/Recursive Method - История изменений
2026-04-21T22:30:28Z
История изменений этой страницы в вики
MediaWiki 1.30.0
http://www.jexp.ru/index.php?title=Java_Tutorial/Class_Definition/Recursive_Method&diff=4244&oldid=prev
Admin: 1 версия
2010-06-01T05:01:03Z
<p>1 версия</p>
<table class="diff diff-contentalign-left" data-mw="interface">
<tr style="vertical-align: top;" lang="ru">
<td colspan="1" style="background-color: white; color:black; text-align: center;">← Предыдущая</td>
<td colspan="1" style="background-color: white; color:black; text-align: center;">Версия 05:01, 1 июня 2010</td>
</tr><tr><td colspan="2" style="text-align: center;" lang="ru"><div class="mw-diff-empty">(нет различий)</div>
</td></tr></table>
Admin
http://www.jexp.ru/index.php?title=Java_Tutorial/Class_Definition/Recursive_Method&diff=4243&oldid=prev
в 17:44, 31 мая 2010
2010-05-31T17:44:27Z
<p></p>
<p><b>Новая страница</b></p><div>== Recursion: a method (function) calls itself ==<br />
<br />
<br />
<br />
<br />
<p>Characteristics of Recursive Methods:</p><br />
<OL><LI>Method calls itself.</LI><LI>When it calls itself, it solves a smaller problem.</LI><LI>There is a smallest problem that the routine can solve it, and return, without calling itself.</LI></OL><br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
public static void main(String[] args) {<br />
int theAnswer = triangle(12);<br />
System.out.println("Triangle=" + theAnswer);<br />
}<br />
public static int triangle(int n) {<br />
if (n == 1)<br />
return 1;<br />
else<br />
return (n + triangle(n - 1));<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>Triangle=78</pre><br />
<br />
<br />
<br />
== Recursion: another example ==<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
public static void main(String[] args) {<br />
double x = 5.0;<br />
System.out.println(x + " to the power 4 is " + power(x, 4));<br />
System.out.println("7.5 to the power 5 is " + power(7.5, 5));<br />
System.out.println("7.5 to the power 0 is " + power(7.5, 0));<br />
System.out.println("10 to the power -2 is " + power(10, -2));<br />
}<br />
// Raise x to the power n<br />
static double power(double x, int n) {<br />
if (n > 1)<br />
return x * power(x, n - 1); // Recursive call<br />
else if (n < 0)<br />
return 1.0 / power(x, -n); // Negative power of x<br />
else<br />
return x;<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>5.0 to the power 4 is 625.0<br />
7.5 to the power 5 is 23730.46875<br />
7.5 to the power 0 is 7.5<br />
10 to the power -2 is 0.01</pre><br />
<br />
<br />
<br />
== Recursive factorial method ==<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
public static void main(String args[]) {<br />
for (int counter = 0; counter <= 10; counter++)<br />
System.out.printf("%d! = %d\n", counter, factorial(counter));<br />
}<br />
// recursive declaration of method factorial<br />
public static long factorial(long number) {<br />
if (number <= 1) // test for base case<br />
return 1; // base cases: 0! = 1 and 1! = 1<br />
else<br />
// recursion step<br />
return number * factorial(number - 1);<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>0! = 1<br />
1! = 1<br />
2! = 2<br />
3! = 6<br />
4! = 24<br />
5! = 120<br />
6! = 720<br />
7! = 5040<br />
8! = 40320<br />
9! = 362880<br />
10! = 3628800</pre><br />
<br />
<br />
<br />
== Recursive fibonacci method ==<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
// recursive declaration of method fibonacci<br />
public static long fibonacci(long number) {<br />
if ((number == 0) || (number == 1)) // base cases<br />
return number;<br />
else<br />
// recursion step<br />
return fibonacci(number - 1) + fibonacci(number - 2);<br />
}<br />
public static void main(String[] args) {<br />
for (int counter = 0; counter <= 10; counter++)<br />
System.out.printf("Fibonacci of %d is: %d\n", counter, fibonacci(counter));<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>Fibonacci of 0 is: 0<br />
Fibonacci of 1 is: 1<br />
Fibonacci of 2 is: 1<br />
Fibonacci of 3 is: 2<br />
Fibonacci of 4 is: 3<br />
Fibonacci of 5 is: 5<br />
Fibonacci of 6 is: 8<br />
Fibonacci of 7 is: 13<br />
Fibonacci of 8 is: 21<br />
Fibonacci of 9 is: 34<br />
Fibonacci of 10 is: 55</pre><br />
<br />
<br />
<br />
== Recursive method to find all permutations of a String ==<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
public static void main(String args[]) {<br />
permuteString("", "String");<br />
}<br />
public static void permuteString(String beginningString, String endingString) {<br />
if (endingString.length() <= 1)<br />
System.out.println(beginningString + endingString);<br />
else<br />
for (int i = 0; i < endingString.length(); i++) {<br />
try {<br />
String newString = endingString.substring(0, i) + endingString.substring(i + 1);<br />
permuteString(beginningString + endingString.charAt(i), newString);<br />
} catch (StringIndexOutOfBoundsException exception) {<br />
exception.printStackTrace();<br />
}<br />
}<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>String<br />
Strign<br />
Strnig<br />
Strngi<br />
Strgin<br />
Strgni<br />
Stirng<br />
Stirgn<br />
Stinrg<br />
Stingr<br />
Stigrn<br />
Stignr<br />
Stnrig<br />
Stnrgi<br />
Stnirg<br />
Stnigr<br />
Stngri<br />
Stngir<br />
Stgrin<br />
Stgrni<br />
Stgirn<br />
Stginr<br />
Stgnri<br />
Stgnir<br />
Srting<br />
Srtign<br />
Srtnig<br />
Srtngi<br />
Srtgin<br />
Srtgni<br />
Sritng<br />
Sritgn<br />
Srintg<br />
Sringt<br />
Srigtn<br />
Srignt<br />
Srntig<br />
Srntgi<br />
Srnitg<br />
Srnigt<br />
Srngti<br />
Srngit<br />
Srgtin<br />
Srgtni<br />
Srgitn<br />
Srgint<br />
Srgnti<br />
Srgnit<br />
Sitrng<br />
Sitrgn<br />
Sitnrg<br />
Sitngr<br />
Sitgrn<br />
Sitgnr<br />
Sirtng<br />
Sirtgn<br />
Sirntg<br />
Sirngt<br />
Sirgtn<br />
Sirgnt<br />
Sintrg<br />
Sintgr<br />
Sinrtg<br />
Sinrgt<br />
Singtr<br />
Singrt<br />
Sigtrn<br />
Sigtnr<br />
Sigrtn<br />
Sigrnt<br />
Signtr<br />
Signrt<br />
Sntrig<br />
Sntrgi<br />
Sntirg<br />
Sntigr<br />
Sntgri<br />
Sntgir<br />
Snrtig<br />
Snrtgi<br />
Snritg<br />
Snrigt<br />
Snrgti<br />
Snrgit<br />
Snitrg<br />
Snitgr<br />
Snirtg<br />
Snirgt<br />
Snigtr<br />
Snigrt<br />
Sngtri<br />
Sngtir<br />
Sngrti<br />
Sngrit<br />
Sngitr<br />
Sngirt<br />
Sgtrin<br />
Sgtrni<br />
Sgtirn<br />
Sgtinr<br />
Sgtnri<br />
Sgtnir<br />
Sgrtin<br />
Sgrtni<br />
Sgritn<br />
Sgrint<br />
Sgrnti<br />
Sgrnit<br />
Sgitrn<br />
Sgitnr<br />
Sgirtn<br />
Sgirnt<br />
Sgintr<br />
Sginrt<br />
Sgntri<br />
Sgntir<br />
Sgnrti<br />
Sgnrit<br />
Sgnitr<br />
Sgnirt<br />
tSring<br />
tSrign<br />
tSrnig<br />
tSrngi<br />
tSrgin<br />
tSrgni<br />
tSirng<br />
tSirgn<br />
tSinrg<br />
tSingr<br />
tSigrn<br />
tSignr<br />
tSnrig<br />
tSnrgi<br />
tSnirg<br />
tSnigr<br />
tSngri<br />
tSngir<br />
tSgrin<br />
tSgrni<br />
tSgirn<br />
tSginr<br />
tSgnri<br />
tSgnir<br />
trSing<br />
trSign<br />
trSnig<br />
trSngi<br />
trSgin<br />
trSgni<br />
triSng<br />
triSgn<br />
trinSg<br />
tringS<br />
trigSn<br />
trignS<br />
trnSig<br />
trnSgi<br />
trniSg<br />
trnigS<br />
trngSi<br />
trngiS<br />
trgSin<br />
trgSni<br />
trgiSn<br />
trginS<br />
trgnSi<br />
trgniS<br />
tiSrng<br />
tiSrgn<br />
tiSnrg<br />
tiSngr<br />
tiSgrn<br />
tiSgnr<br />
tirSng<br />
tirSgn<br />
tirnSg<br />
tirngS<br />
tirgSn<br />
tirgnS<br />
tinSrg<br />
tinSgr<br />
tinrSg<br />
tinrgS<br />
tingSr<br />
tingrS<br />
tigSrn<br />
tigSnr<br />
tigrSn<br />
tigrnS<br />
tignSr<br />
tignrS<br />
tnSrig<br />
tnSrgi<br />
tnSirg<br />
tnSigr<br />
tnSgri<br />
tnSgir<br />
tnrSig<br />
tnrSgi<br />
tnriSg<br />
tnrigS<br />
tnrgSi<br />
tnrgiS<br />
tniSrg<br />
tniSgr<br />
tnirSg<br />
tnirgS<br />
tnigSr<br />
tnigrS<br />
tngSri<br />
tngSir<br />
tngrSi<br />
tngriS<br />
tngiSr<br />
tngirS<br />
tgSrin<br />
tgSrni<br />
tgSirn<br />
tgSinr<br />
tgSnri<br />
tgSnir<br />
tgrSin<br />
tgrSni<br />
tgriSn<br />
tgrinS<br />
tgrnSi<br />
tgrniS<br />
tgiSrn<br />
tgiSnr<br />
tgirSn<br />
tgirnS<br />
tginSr<br />
tginrS<br />
tgnSri<br />
tgnSir<br />
tgnrSi<br />
tgnriS<br />
tgniSr<br />
tgnirS<br />
rSting<br />
rStign<br />
rStnig<br />
rStngi<br />
rStgin<br />
rStgni<br />
rSitng<br />
rSitgn<br />
rSintg<br />
rSingt<br />
rSigtn<br />
rSignt<br />
rSntig<br />
rSntgi<br />
rSnitg<br />
rSnigt<br />
rSngti<br />
rSngit<br />
rSgtin<br />
rSgtni<br />
rSgitn<br />
rSgint<br />
rSgnti<br />
rSgnit<br />
rtSing<br />
rtSign<br />
rtSnig<br />
rtSngi<br />
rtSgin<br />
rtSgni<br />
rtiSng<br />
rtiSgn<br />
rtinSg<br />
rtingS<br />
rtigSn<br />
rtignS<br />
rtnSig<br />
rtnSgi<br />
rtniSg<br />
rtnigS<br />
rtngSi<br />
rtngiS<br />
rtgSin<br />
rtgSni<br />
rtgiSn<br />
rtginS<br />
rtgnSi<br />
rtgniS<br />
riStng<br />
riStgn<br />
riSntg<br />
riSngt<br />
riSgtn<br />
riSgnt<br />
ritSng<br />
ritSgn<br />
ritnSg<br />
ritngS<br />
ritgSn<br />
ritgnS<br />
rinStg<br />
rinSgt<br />
rintSg<br />
rintgS<br />
ringSt<br />
ringtS<br />
rigStn<br />
rigSnt<br />
rigtSn<br />
rigtnS<br />
rignSt<br />
rigntS<br />
rnStig<br />
rnStgi<br />
rnSitg<br />
rnSigt<br />
rnSgti<br />
rnSgit<br />
rntSig<br />
rntSgi<br />
rntiSg<br />
rntigS<br />
rntgSi<br />
rntgiS<br />
rniStg<br />
rniSgt<br />
rnitSg<br />
rnitgS<br />
rnigSt<br />
rnigtS<br />
rngSti<br />
rngSit<br />
rngtSi<br />
rngtiS<br />
rngiSt<br />
rngitS<br />
rgStin<br />
rgStni<br />
rgSitn<br />
rgSint<br />
rgSnti<br />
rgSnit<br />
rgtSin<br />
rgtSni<br />
rgtiSn<br />
rgtinS<br />
rgtnSi<br />
rgtniS<br />
rgiStn<br />
rgiSnt<br />
rgitSn<br />
rgitnS<br />
rginSt<br />
rgintS<br />
rgnSti<br />
rgnSit<br />
rgntSi<br />
rgntiS<br />
rgniSt<br />
rgnitS<br />
iStrng<br />
iStrgn<br />
iStnrg<br />
iStngr<br />
iStgrn<br />
iStgnr<br />
iSrtng<br />
iSrtgn<br />
iSrntg<br />
iSrngt<br />
iSrgtn<br />
iSrgnt<br />
iSntrg<br />
iSntgr<br />
iSnrtg<br />
iSnrgt<br />
iSngtr<br />
iSngrt<br />
iSgtrn<br />
iSgtnr<br />
iSgrtn<br />
iSgrnt<br />
iSgntr<br />
iSgnrt<br />
itSrng<br />
itSrgn<br />
itSnrg<br />
itSngr<br />
itSgrn<br />
itSgnr<br />
itrSng<br />
itrSgn<br />
itrnSg<br />
itrngS<br />
itrgSn<br />
itrgnS<br />
itnSrg<br />
itnSgr<br />
itnrSg<br />
itnrgS<br />
itngSr<br />
itngrS<br />
itgSrn<br />
itgSnr<br />
itgrSn<br />
itgrnS<br />
itgnSr<br />
itgnrS<br />
irStng<br />
irStgn<br />
irSntg<br />
irSngt<br />
irSgtn<br />
irSgnt<br />
irtSng<br />
irtSgn<br />
irtnSg<br />
irtngS<br />
irtgSn<br />
irtgnS<br />
irnStg<br />
irnSgt<br />
irntSg<br />
irntgS<br />
irngSt<br />
irngtS<br />
irgStn<br />
irgSnt<br />
irgtSn<br />
irgtnS<br />
irgnSt<br />
irgntS<br />
inStrg<br />
inStgr<br />
inSrtg<br />
inSrgt<br />
inSgtr<br />
inSgrt<br />
intSrg<br />
intSgr<br />
intrSg<br />
intrgS<br />
intgSr<br />
intgrS<br />
inrStg<br />
inrSgt<br />
inrtSg<br />
inrtgS<br />
inrgSt<br />
inrgtS<br />
ingStr<br />
ingSrt<br />
ingtSr<br />
ingtrS<br />
ingrSt<br />
ingrtS<br />
igStrn<br />
igStnr<br />
igSrtn<br />
igSrnt<br />
igSntr<br />
igSnrt<br />
igtSrn<br />
igtSnr<br />
igtrSn<br />
igtrnS<br />
igtnSr<br />
igtnrS<br />
igrStn<br />
igrSnt<br />
igrtSn<br />
igrtnS<br />
igrnSt<br />
igrntS<br />
ignStr<br />
ignSrt<br />
igntSr<br />
igntrS<br />
ignrSt<br />
ignrtS<br />
nStrig<br />
nStrgi<br />
nStirg<br />
nStigr<br />
nStgri<br />
nStgir<br />
nSrtig<br />
nSrtgi<br />
nSritg<br />
nSrigt<br />
nSrgti<br />
nSrgit<br />
nSitrg<br />
nSitgr<br />
nSirtg<br />
nSirgt<br />
nSigtr<br />
nSigrt<br />
nSgtri<br />
nSgtir<br />
nSgrti<br />
nSgrit<br />
nSgitr<br />
nSgirt<br />
ntSrig<br />
ntSrgi<br />
ntSirg<br />
ntSigr<br />
ntSgri<br />
ntSgir<br />
ntrSig<br />
ntrSgi<br />
ntriSg<br />
ntrigS<br />
ntrgSi<br />
ntrgiS<br />
ntiSrg<br />
ntiSgr<br />
ntirSg<br />
ntirgS<br />
ntigSr<br />
ntigrS<br />
ntgSri<br />
ntgSir<br />
ntgrSi<br />
ntgriS<br />
ntgiSr<br />
ntgirS<br />
nrStig<br />
nrStgi<br />
nrSitg<br />
nrSigt<br />
nrSgti<br />
nrSgit<br />
nrtSig<br />
nrtSgi<br />
nrtiSg<br />
nrtigS<br />
nrtgSi<br />
nrtgiS<br />
nriStg<br />
nriSgt<br />
nritSg<br />
nritgS<br />
nrigSt<br />
nrigtS<br />
nrgSti<br />
nrgSit<br />
nrgtSi<br />
nrgtiS<br />
nrgiSt<br />
nrgitS<br />
niStrg<br />
niStgr<br />
niSrtg<br />
niSrgt<br />
niSgtr<br />
niSgrt<br />
nitSrg<br />
nitSgr<br />
nitrSg<br />
nitrgS<br />
nitgSr<br />
nitgrS<br />
nirStg<br />
nirSgt<br />
nirtSg<br />
nirtgS<br />
nirgSt<br />
nirgtS<br />
nigStr<br />
nigSrt<br />
nigtSr<br />
nigtrS<br />
nigrSt<br />
nigrtS<br />
ngStri<br />
ngStir<br />
ngSrti<br />
ngSrit<br />
ngSitr<br />
ngSirt<br />
ngtSri<br />
ngtSir<br />
ngtrSi<br />
ngtriS<br />
ngtiSr<br />
ngtirS<br />
ngrSti<br />
ngrSit<br />
ngrtSi<br />
ngrtiS<br />
ngriSt<br />
ngritS<br />
ngiStr<br />
ngiSrt<br />
ngitSr<br />
ngitrS<br />
ngirSt<br />
ngirtS<br />
gStrin<br />
gStrni<br />
gStirn<br />
gStinr<br />
gStnri<br />
gStnir<br />
gSrtin<br />
gSrtni<br />
gSritn<br />
gSrint<br />
gSrnti<br />
gSrnit<br />
gSitrn<br />
gSitnr<br />
gSirtn<br />
gSirnt<br />
gSintr<br />
gSinrt<br />
gSntri<br />
gSntir<br />
gSnrti<br />
gSnrit<br />
gSnitr<br />
gSnirt<br />
gtSrin<br />
gtSrni<br />
gtSirn<br />
gtSinr<br />
gtSnri<br />
gtSnir<br />
gtrSin<br />
gtrSni<br />
gtriSn<br />
gtrinS<br />
gtrnSi<br />
gtrniS<br />
gtiSrn<br />
gtiSnr<br />
gtirSn<br />
gtirnS<br />
gtinSr<br />
gtinrS<br />
gtnSri<br />
gtnSir<br />
gtnrSi<br />
gtnriS<br />
gtniSr<br />
gtnirS<br />
grStin<br />
grStni<br />
grSitn<br />
grSint<br />
grSnti<br />
grSnit<br />
grtSin<br />
grtSni<br />
grtiSn<br />
grtinS<br />
grtnSi<br />
grtniS<br />
griStn<br />
griSnt<br />
gritSn<br />
gritnS<br />
grinSt<br />
grintS<br />
grnSti<br />
grnSit<br />
grntSi<br />
grntiS<br />
grniSt<br />
grnitS<br />
giStrn<br />
giStnr<br />
giSrtn<br />
giSrnt<br />
giSntr<br />
giSnrt<br />
gitSrn<br />
gitSnr<br />
gitrSn<br />
gitrnS<br />
gitnSr<br />
gitnrS<br />
girStn<br />
girSnt<br />
girtSn<br />
girtnS<br />
girnSt<br />
girntS<br />
ginStr<br />
ginSrt<br />
gintSr<br />
gintrS<br />
ginrSt<br />
ginrtS<br />
gnStri<br />
gnStir<br />
gnSrti<br />
gnSrit<br />
gnSitr<br />
gnSirt<br />
gntSri<br />
gntSir<br />
gntrSi<br />
gntriS<br />
gntiSr<br />
gntirS<br />
gnrSti<br />
gnrSit<br />
gnrtSi<br />
gnrtiS<br />
gnriSt<br />
gnritS<br />
gniStr<br />
gniSrt<br />
gnitSr<br />
gnitrS<br />
gnirSt<br />
gnirtS</pre><br />
<br />
<br />
<br />
== The Towers of Hanoi ==<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<!-- start source code --><br />
<br />
<source lang="java"><br />
public class MainClass {<br />
public static void main(String[] args) {<br />
int nDisks = 3;<br />
doTowers(nDisks, "A", "B", "C");<br />
}<br />
public static void doTowers(int topN, char from, char inter, char to) {<br />
if (topN == 1){<br />
System.out.println("Disk 1 from " + from + " to " + to);<br />
}else {<br />
doTowers(topN - 1, from, to, inter);<br />
System.out.println("Disk " + topN + " from " + from + " to " + to);<br />
doTowers(topN - 1, inter, from, to);<br />
}<br />
}<br />
}</source><br />
<br />
<br />
<!-- end source code --><br />
<br />
<br />
<pre class=codeResult>Disk 1 from A to C<br />
Disk 2 from A to B<br />
Disk 1 from C to B<br />
Disk 3 from A to C<br />
Disk 1 from B to A<br />
Disk 2 from B to C<br />
Disk 1 from A to C</pre></div>