给定一个数字输入字符串,找到可以使用数字以相同顺序形成的所有数字组合。
例子:
Input : 123
Output :1 2 3
1 23
12 3
123
Input : 1234
Output : 1 2 3 4
1 2 34
1 23 4
1 234
12 3 4
12 34
123 4
1234
可以使用递归来解决该问题。到目前为止,我们一直跟踪给定输入字符串中的当前索引以及输出字符串的长度。在每次调用该函数,如果输入字符串中没有剩余数字,请打印当前输出字符串并返回。否则,将当前数字复制到输出。从这里打两次电话,一个将下一位数字视为下一个数字的一部分(包括输出字符串),一个将下一位数字视为当前数字的一部分(不包括空格)。如果在当前数字之后没有剩余数字,则将省略对函数的第二次调用,因为尾部空格不会算作新的组合。
C++
// CPP program to find all combination of numbers
// from a given string of digits
#include
#include
using namespace std;
// function to print combinations of numbers
// in given input string
void printCombinations(char* input, int index,
char* output, int outLength)
{
// no more digits left in input string
if (input[index] == '\0')
{
// print output string & return
output[outLength] = '\0';
cout << output << endl;
return;
}
// place current digit in input string
output[outLength] = input[index];
// separate next digit with a space
output[outLength + 1] = ' ';
printCombinations(input, index + 1, output,
outLength + 2);
// if next digit exists make a
// call without including space
if(input[index + 1] != '\0')
printCombinations(input, index + 1, output,
outLength + 1);
}
// driver function to test above function
int main()
{
char input[] = "1214";
char *output = new char[100];
// initialize output with empty string
output[0] = '\0';
printCombinations(input, 0, output, 0);
return 0;
}
Java
// Java program to find all combinations
// of numbers from a given string of digits
class GFG
{
// function to print combinations of numbers
// in given input string
static void printCombinations(char[] input,
int index,
char[] output,
int outLength)
{
// no more digits left in input string
if (input.length == index)
{
// print output string & return
System.out.println(String.valueOf(output));
return;
}
// place current digit in input string
output[outLength] = input[index];
// separate next digit with a space
output[outLength + 1] = ' ';
printCombinations(input, index + 1, output,
outLength + 2);
// if next digit exists make a
// call without including space
if(input.length!=index + 1)
printCombinations(input, index + 1, output,
outLength + 1);
}
// Driver Code
public static void main(String[] args)
{
char input[] = "1214".toCharArray();
char []output = new char[100];
printCombinations(input, 0, output, 0);
}
}
// This code is contributed by Rajput-Ji
Python3
# Python3 program to find all combination of numbers
# from a given string of digits
# function to print combinations of numbers
# in given input string
def printCombinations(input, index, output, outLength):
# no more digits left in input string
if (len(input) == index):
# print output string & return
output[outLength] = '\0'
print(*output[:outLength], sep = "")
return
# place current digit in input string
output[outLength] = input[index]
# separate next digit with a space
output[outLength + 1] = ' '
printCombinations(input, index + 1,
output, outLength + 2)
# if next digit exists make a
# call without including space
if(len(input) != (index + 1)):
printCombinations(input, index + 1,
output, outLength + 1)
# Driver code
input = "1214"
output = [0]*100
# initialize output with empty string
output[0] = '\0'
printCombinations(input, 0, output, 0)
# This code is contributed by SHUBHAMSINGH10
C#
// C# program to find all combinations
// of numbers from a given string of digits
using System;
class GFG
{
// function to print combinations of numbers
// in given input string
static void printCombinations(char[] input,
int index,
char[] output,
int outLength)
{
// no more digits left in input string
if (input.Length == index)
{
// print output string & return
Console.WriteLine(String.Join("",
output));
return;
}
// place current digit in input string
output[outLength] = input[index];
// separate next digit with a space
output[outLength + 1] = ' ';
printCombinations(input, index + 1, output,
outLength + 2);
// if next digit exists make a
// call without including space
if(input.Length!=index + 1)
printCombinations(input, index + 1, output,
outLength + 1);
}
// Driver Code
public static void Main(String[] args)
{
char []input = "1214".ToCharArray();
char []output = new char[100];
printCombinations(input, 0, output, 0);
}
}
// This code is contributed by 29AjayKumar
Javascript
C++
// CPP program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
#include
using namespace std;
// function to print combinations of
// numbers in given input string
void printCombinations(char s[]){
// find length of char array
int l = strlen(s);
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0; i < pow(2, l - 1); i++){
int k = i, x = 0;
// first character will be printed
// as well
cout << s[x];
x++;
for(int j = 0; j < strlen(s) - 1; j++){
// if bit is set, means provide
// space
if(k & 1)
cout << " ";
k = k >> 1;
cout << s[x];
// always increment index of
// input string
x++;
}
cout << "\n";
}
}
// driver code
int main() {
char input[] = "1214";
printCombinations(input);
return 0;
}
// This code is contributed by PRINCE Gupta 2
Java
// Java program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
import java.util.*;
class GFG
{
// function to print combinations of
// numbers in given input string
static void printCombinations(char s[])
{
// find length of char array
int l = s.length;
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0;
i < Math.pow(2, l - 1); i++)
{
int k = i, x = 0;
// first character will be printed
// as well
System.out.print(s[x]);
x++;
for(int j = 0;
j < s.length - 1; j++)
{
// if bit is set, means provide
// space
if(k % 2 == 1)
System.out.print(" ");
k = k >> 1;
System.out.print(s[x]);
// always increment index of
// input string
x++;
}
System.out.print("\n");
}
}
// Driver Code
public static void main(String[] args)
{
char input[] = "1214".toCharArray();
printCombinations(input);
}
}
// This code is contributed by PrinciRaj1992
Python3
# Python 3 program to find all
# combination of numbers from
# a given string of digits using
# bit algorithm used same logic
# as to print power set of string
# Function to print combinations of
# numbers in given input string
def printCombinations(s):
# find length of char array
l = len(s);
# we can give space between
# characters ex. ('1' & '2')
# or ('2' & '3') or ('3' & '4')
# or ('3' & '4') or all that`s
# why here we have maximum
# space length - 1
for i in range(pow(2, l - 1)):
k = i
x = 0
# first character will
# be printed as well
print(s[x], end = "")
x += 1
for j in range(len(s) - 1):
# if bit is set, means
# provide space
if(k & 1):
print(" ", end = "")
k = k >> 1
print(s[x], end = "")
# always increment index of
# input string
x += 1
print()
# Driver code
if __name__ == "__main__":
inp = "1214";
printCombinations(inp);
# This code is contributed by Chitranayal
C#
// C# program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
using System;
class GFG
{
// function to print combinations of
// numbers in given input string
static void printCombinations(char []s)
{
// find length of char array
int l = s.Length;
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0;
i < Math.Pow(2, l - 1); i++)
{
int k = i, x = 0;
// first character will be printed
// as well
Console.Write(s[x]);
x++;
for(int j = 0;
j < s.Length - 1; j++)
{
// if bit is set, means provide
// space
if(k % 2 == 1)
Console.Write(" ");
k = k >> 1;
Console.Write(s[x]);
// always increment index of
// input string
x++;
}
Console.Write("\n");
}
}
// Driver Code
public static void Main(String[] args)
{
char []input = "1214".ToCharArray();
printCombinations(input);
}
}
// This code is contributed by Rajput-Ji
Javascript
输出:
1 2 1 4
1 2 14
1 21 4
1 214
12 1 4
12 14
121 4
1214
替代解决方案:
C++
// CPP program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
#include
using namespace std;
// function to print combinations of
// numbers in given input string
void printCombinations(char s[]){
// find length of char array
int l = strlen(s);
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0; i < pow(2, l - 1); i++){
int k = i, x = 0;
// first character will be printed
// as well
cout << s[x];
x++;
for(int j = 0; j < strlen(s) - 1; j++){
// if bit is set, means provide
// space
if(k & 1)
cout << " ";
k = k >> 1;
cout << s[x];
// always increment index of
// input string
x++;
}
cout << "\n";
}
}
// driver code
int main() {
char input[] = "1214";
printCombinations(input);
return 0;
}
// This code is contributed by PRINCE Gupta 2
Java
// Java program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
import java.util.*;
class GFG
{
// function to print combinations of
// numbers in given input string
static void printCombinations(char s[])
{
// find length of char array
int l = s.length;
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0;
i < Math.pow(2, l - 1); i++)
{
int k = i, x = 0;
// first character will be printed
// as well
System.out.print(s[x]);
x++;
for(int j = 0;
j < s.length - 1; j++)
{
// if bit is set, means provide
// space
if(k % 2 == 1)
System.out.print(" ");
k = k >> 1;
System.out.print(s[x]);
// always increment index of
// input string
x++;
}
System.out.print("\n");
}
}
// Driver Code
public static void main(String[] args)
{
char input[] = "1214".toCharArray();
printCombinations(input);
}
}
// This code is contributed by PrinciRaj1992
Python3
# Python 3 program to find all
# combination of numbers from
# a given string of digits using
# bit algorithm used same logic
# as to print power set of string
# Function to print combinations of
# numbers in given input string
def printCombinations(s):
# find length of char array
l = len(s);
# we can give space between
# characters ex. ('1' & '2')
# or ('2' & '3') or ('3' & '4')
# or ('3' & '4') or all that`s
# why here we have maximum
# space length - 1
for i in range(pow(2, l - 1)):
k = i
x = 0
# first character will
# be printed as well
print(s[x], end = "")
x += 1
for j in range(len(s) - 1):
# if bit is set, means
# provide space
if(k & 1):
print(" ", end = "")
k = k >> 1
print(s[x], end = "")
# always increment index of
# input string
x += 1
print()
# Driver code
if __name__ == "__main__":
inp = "1214";
printCombinations(inp);
# This code is contributed by Chitranayal
C#
// C# program to find all combination of
// numbers from a given string of digits
// using bit algorithm used same logic
// as to print power set of string
using System;
class GFG
{
// function to print combinations of
// numbers in given input string
static void printCombinations(char []s)
{
// find length of char array
int l = s.Length;
// we can give space between characters
// ex. ('1' & '2') or ('2' & '3') or
// ('3' & '4') or ('3' & '4') or all
// that`s why here we have maximum
// space length - 1
for(int i = 0;
i < Math.Pow(2, l - 1); i++)
{
int k = i, x = 0;
// first character will be printed
// as well
Console.Write(s[x]);
x++;
for(int j = 0;
j < s.Length - 1; j++)
{
// if bit is set, means provide
// space
if(k % 2 == 1)
Console.Write(" ");
k = k >> 1;
Console.Write(s[x]);
// always increment index of
// input string
x++;
}
Console.Write("\n");
}
}
// Driver Code
public static void Main(String[] args)
{
char []input = "1214".ToCharArray();
printCombinations(input);
}
}
// This code is contributed by Rajput-Ji
Java脚本
输出:
1214
1 214
12 14
1 2 14
121 4
1 21 4
12 1 4
1 2 1 4