Given a string which consists of either ‘.’ or any number. A ‘.’ in the string means that the cell is empty and if there is a number in any cell, it means one can move steps to right or left within the string.
The task is to check if any cell in the string can be visited more than once. If so, print YES otherwise print NO.
Input : str = ".2...2.." Output: YES The fourth cell can be visited twice. One way to reach the fourth cell is from 2nd cell by moving 2 steps to right and another way to reach fourth cell is by moving 2 steps left from cell 6. Input : str = ".2...1" Output: NO None of the cells in the given string can be visited more than once.
The idea is to take an array visited to keep track of the number of times i-th cell of the string can be visited. Now traverse the string and check if the current character is a ‘.’ or a number . If the current character is a ‘.’ then do nothing otherwise if it is a number then increase the count of visits in the visited array within the range [i-x, i+x] by 1.
Finally, traverse the visited array and check if any cell is visited more than once.
Below is the implementation of the above approach:
- Check if a Queen can attack a given cell on chessboard
- Check if any square (with one colored cell) can be divided into two equal parts
- Printing pre and post visited times in DFS of a graph
- Count the total number of squares that can be visited by Bishop in one move
- Check if a string contains a palindromic sub-string of even length
- Final cell position in the matrix
- Check if a string has m consecutive 1's or 0's
- Check if it is possible to convert one string into another with given constraints
- Check if all the 1's in a binary string are equidistant or not
- Check whether the frequencies of all the characters in a string are prime or not
- Check if the characters of a given string are in alphabetical order
- Check whether the vowels in a string are in alphabetical order or not
- Check if a string can be rearranged to form special palindrome
- Check whether count of distinct characters in a string is Prime or not
- Check if string can be made lexicographically smaller by reversing any substring
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.