Sort groups of numbers and characters separately in a String
Given a string str of alphanumeric characters, the task is to sort the similar group of consecutive characters separately and print the modified string i.e. all consecutive groups of digits and alphabetical characters will be sorted separately.
Examples:
Input: str = “121geeks21”
Output: 112eegks12
“121”, “geeks”, “21” are the valid groups
and they will be sorted separately.
Input: str = “cba321ab”
Output: abc123ab
Approach: Create a vector to store the starting indices of all the valid groups in the given string. Now, traverse the string character by character and if the current character is from a different group than the previous character then push the current index to the vector. After the string has been traversed completely, sort all the individual groups of substring of the given string using the vector updated earlier. Finally, print the modified string.
Below is the implementation of the above approach:
CPP
// C++ implementation of the approach#include <bits/stdc++.h>using namespace std;// Function to return the modified stringstring get_string(string str, int n){ // To store the previous character char prev = str[0]; // To store the starting indices // of all the groups vector<int> result; // Starting index of the first group result.push_back(0); for (int i = 1; i < n; i++) { // If the current character and the // previous character differ if (isdigit(str[i]) != isdigit(prev)) { // Push the starting index // of the new group result.push_back(i); } // The current character now becomes previous prev = str[i]; } // Sort the first group sort(str.begin(), str.begin() + result[0]); // Sort all the remaining groups for (int i = 0; i < result.size() - 1; i++) { sort(str.begin() + result[i], str.begin() + result[i + 1]); } //cout<<str<<endl; // Sort the last group sort(str.begin() + result[result.size() - 1], str.end()); // Return the modified string return str;}// Driver codeint main(){ string str = "121geeks21"; int n = str.length(); cout << get_string(str, n); return 0;} |
Python3
# Python 3 implementation of the approach# Function to return the modified stringdef get_string(st, n): # To store the previous character prev = st[0] # To store the starting indices # of all the groups result = [] # Starting index of the first group result.append(0) for i in range(1, n): # If the current character and the # previous character differ if (st[i].isdigit() != prev.isdigit()): # Push the starting index # of the new group result.append(i) # The current character now becomes previous prev = st[i] # Sort the first group st = list(st) st[:result[0]].sort() p = st.copy() # Sort all the remaining groups for i in range(len(result)-1): p[result[i]:result[i+1]] = sorted(st[result[i]:result[i+1]]) # print(''.join(st)) # Sort the last group p[len(p)-2:] = sorted(st[result[-1]:]) # Return the modified string return ''.join(p)# Driver codeif __name__ == "__main__": st = "121geeks21" n = len(st) print(get_string(st, n)) # This code is contributed by ukasp. |
112eegks12
Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.
In case you wish to attend live classes with experts, please refer DSA Live Classes for Working Professionals and Competitive Programming Live for Students.
