在本節中，我們將看到如何產生任意長度的所有可能字串，這將採用每個字元的組合來產生字串。例如，如果字串是ABC，則它將產生- {A，B，C，AB，BA，BC，CB，CA，AC，ABC，ACB，BAC，BCA，CAB，CBA}
讓我們來看一個例子來理解。
Begin
n := length of the string str
count is 2^n – 1
for each number 0 to count, do
sub_str := empty string
for j in range 0 to n, do
if jth bit of the counter is set, then
concatenate jth character of str with sub_str
end if
done
repeat:
print sub_string
until next permutation of sub_string is not completed
done
End#include <iostream>
#include <algorithm>
#include <cmath>
using namespace std;
void printAllString(string str) {
int n = str.size();
unsigned int count = pow(2, n);
for (int counter = 1; counter <count; counter++) { //generate 2^n - 1 strings
string subs = "";
for (int j = 0; j < n; j++) {
if (counter & (1<<j)) //when the jth bit is set, then add jth character
subs.push_back(str[j]);
}
do{
cout << subs << endl;
}
while (next_permutation(subs.begin(), subs.end()));
}
}A B AB BA C AC CA BC CB ABC ACB BAC BCA CAB CBA D AD DA BD DB ABD ADB BAD BDA DAB DBA CD DC ACD ADC CAD CDA DAC DCA BCD BDC CBD CDB DBC DCB ABCD ABDC ACBD ACDB ADBC ADCB BACD BADC BCAD BCDA BDAC BDCA CABD CADB CBAD CBDA CDAB CDBA DABC DACB DBAC DBCA DCAB DCBA
以上是給定一個字串，將其組成的所有可能長度的字串都列出來的詳細內容。更多資訊請關注PHP中文網其他相關文章！
