Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
C++ Program to check string is strictly alphabetical or not
Suppose we have a string S with n letters in lowercase. A string is strictly alphabetical string, if it follows the following rule −
Write an empty string to T
Then perform the next step n times;
At the i-th step take i-th lowercase letter of the Latin alphabet and insert it either to the left of the string T or to the right of the string T (c is the i-th letter of the Latin alphabet).
We have to check whether S is strictly alphabetical string or not.
Problem Category
To solve this problem, we need to manipulate strings. Strings in a programming language are a stream of characters that are stored in a particular array-like data type. Several languages specify strings as a specific data type (eg. Java, C++, Python); and several other languages specify strings as a character array (eg. C). Strings are instrumental in programming as they often are the preferred data type in various applications and are used as the datatype for input and output. There are various string operations, such as string searching, substring generation, string stripping operations, string translation operations, string replacement operations, string reverse operations, and much more. Check out the links below to understand how strings can be used in C/C++.
https://www.tutorialspoint.com/cplusplus/cpp_strings.htm
https://www.tutorialspoint.com/cprogramming/c_strings.htm
So, if the input of our problem is like S = "ihfcbadeg", then the output will be True.
Steps
To solve this, we will follow these steps −
len := size of S for initialize i := len, when i >= 1, update (decrease i by 1), do: if S[l] is the i th character, then: (increase l by 1) otherwise when S[r] is the ith character, then: (decrease r by 1) Otherwise Come out from the loop if i is same as 0, then: return true Otherwise return false
Example
Let us see the following implementation to get better understanding −
#include <bits/stdc++.h>
using namespace std;
bool solve(string S){
int len = S.size(), l = 0, r = len - 1, i;
for (i = len; i >= 1; i--){
if (S[l] - 'a' + 1 == i)
l++;
else if (S[r] - 'a' + 1 == i)
r--;
else
break;
}
if (i == 0)
return true;
else
return false;
}
int main(){
string S = "ihfcbadeg";
cout << solve(S) << endl;
}Input
"ihfcbadeg"
Output
1
236 Views
