# Sub-strings having exactly k characters that have ASCII value greater than p

Given a string ‘str’, two integers ‘k’ and ‘p’. The task is to count all the sub-strings of ‘str’ having exactly ‘k’ characters that have ASCII value greater than ‘p’.

Examples:

Input: str = “abcd”, k=2, p=98
Output: 3
Only the characters ‘c’ and ‘d’ have ASCII values greater than 98,
And, the sub-strings containing them are “abcd”, “bcd” and “cd”.

Input: str = “sabrcd”, k=5, p=80
Output: 2

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: We just need to iterate over all indices and take all possible length sub-strings and then just check whether the sub-string has exactly ‘k’ characters that have ASCII value greater than ‘p’.

Typecasting a character to int will give us it’s ASCII value i.e. `int ascii = (int) char`.

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function that checks if ` `// the string contain exactly ` `// K characters having ASCII ` `// value greater than p ` `bool` `isValidSubString(string r, ``int` `K, ``int` `p) ` `{ ` `    ``int` `c = 0; ` ` `  `    ``for` `(``int` `i = 0; i < r.length(); i++) { ` ` `  `        ``// if ASCII value is ` `        ``// greater than 'p' ` `        ``if` `((``int``)r[i] > p) ` `            ``c++; ` `    ``} ` ` `  `    ``// if count of satisfying ` `    ``// characters is equal to 'K' ` `    ``// then return true ` `    ``if` `(c == K) ` `        ``return` `true``; ` ` `  `    ``// otherwise return false ` `    ``else` `        ``return` `false``; ` `} ` ` `  `// function to count sub-strings ` `void` `countSubStrings(string s, ``int` `K, ``int` `p) ` `{ ` `    ``// length of the string ` `    ``int` `l = s.length(); ` ` `  `    ``// count of sub-strings ` `    ``int` `count = 0; ` ` `  `    ``// 'i' is the starting ` `    ``// index for the sub-string ` `    ``for` `(``int` `i = 0; i < l; i++) { ` ` `  `        ``// 'j' is the no. of characters ` `        ``// to include in the sub-string ` `        ``for` `(``int` `j = K; (i + j) <= l; j++) { ` `            ``string r = s.substr(i, j); ` ` `  `            ``// check if the sub-string ` `            ``// satisfies the condition ` `            ``if` `(isValidSubString(r, K, p)) ` `                ``count++; ` `        ``} ` `    ``} ` ` `  `    ``cout << count << ``"\n"``; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` ` `  `    ``string s = ``"abepztydba"``; ` `    ``int` `K = 4; ` `    ``int` `p = 110; ` ` `  `    ``countSubStrings(s, K, p); ` ` `  `    ``return` `0; ` `} `

## Java

 `// Java implementation of the approach ` `class` `GFG { ` ` `  `    ``// Function that checks if ` `    ``// the String contain exactly ` `    ``// K characters having ASCII ` `    ``// value greater than p ` `    ``boolean` `isValidSubString(String r, ``int` `K, ``int` `p) ` `    ``{ ` `        ``int` `c = ``0``; ` ` `  `        ``for` `(``int` `i = ``0``; i < r.length(); i++) { ` ` `  `            ``// if ASCII value is ` `            ``// greater than 'p' ` `            ``if` `((``int``)r.charAt(i) > p) { ` `                ``c++; ` `            ``} ` `        ``} ` ` `  `        ``// if count of satisfying ` `        ``// characters is equal to 'K' ` `        ``// then return true ` `        ``if` `(c == K) { ` `            ``return` `true``; ` `        ``} ` ` `  `        ``// otherwise return false ` `        ``else` `{ ` `            ``return` `false``; ` `        ``} ` `    ``} ` ` `  `    ``// function to count sub-Strings ` `    ``void` `countSubStrings(String s, ``int` `K, ``int` `p) ` `    ``{ ` `        ``// length of the String ` `        ``int` `l = s.length(); ` ` `  `        ``// count of sub-Strings ` `        ``int` `count = ``0``; ` ` `  `        ``// 'i' is the starting ` `        ``// index for the sub-String ` `        ``for` `(``int` `i = ``0``; i < l; i++) { ` ` `  `            ``// 'j' is the no. of characters ` `            ``// to include in the sub-String ` `            ``for` `(``int` `j = K; (i + j) <= l; j++) { ` ` `  `                ``String r = s.substring(i, (i + j)); ` ` `  `                ``// check if the sub-String ` `                ``// satisfies the condition ` `                ``if` `(isValidSubString(r, K, p)) { ` `                    ``count++; ` `                ``} ` `            ``} ` `        ``} ` `        ``System.out.println(count); ` `    ``} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `main(String args[]) ` `    ``{ ` `        ``GFG g = ``new` `GFG(); ` `        ``String s = ``"abepztydba"``; ` `        ``int` `K = ``4``; ` `        ``int` `p = ``110``; ` ` `  `        ``g.countSubStrings(s, K, p); ` `    ``} ` `} ` ` `  `// This code has been contributed by 29AjayKumar `

## Python3

 `# Python3 implementation of the approach  ` ` `  `# Function that checks if the string ` `# contain exactly K characters having ` `# ASCII value greater than p  ` `def` `isValidSubString(r, K, p):  ` ` `  `    ``c ``=` `0` `    ``for` `i ``in` `range``(``0``, ``len``(r)):  ` ` `  `        ``# if ASCII value is  ` `        ``# greater than 'p'  ` `        ``if` `ord``(r[i]) > p: ` `            ``c ``+``=` `1` ` `  `    ``# if count of satisfying  ` `    ``# characters is equal to 'K'  ` `    ``# then return true  ` `    ``if` `c ``=``=` `K: ` `        ``return` `True` ` `  `    ``# otherwise return false  ` `    ``else``: ` `        ``return` `False` ` `  `# function to count sub-strings  ` `def` `countSubStrings(s, K, p):  ` ` `  `    ``# length of the string  ` `    ``l ``=` `len``(s)  ` ` `  `    ``# count of sub-strings  ` `    ``count ``=` `0` ` `  `    ``# 'i' is the starting  ` `    ``# index for the sub-string  ` `    ``for` `i ``in` `range``(``0``, l):  ` ` `  `        ``# 'j' is the no. of characters  ` `        ``# to include in the sub-string  ` `        ``for` `j ``in` `range``(K, l ``-` `i ``+` `1``):  ` `            ``r ``=` `s[i:i ``+` `j]  ` ` `  `            ``# check if the sub-string  ` `            ``# satisfies the condition  ` `            ``if` `isValidSubString(r, K, p) ``=``=` `True``:  ` `                ``count ``+``=` `1` ` `  `    ``print``(count) ` ` `  `# Driver code  ` `if` `__name__ ``=``=` `"__main__"``:  ` ` `  `    ``s ``=` `"abepztydba"` `    ``K, p ``=` `4``, ``110` ` `  `    ``countSubStrings(s, K, p)  ` ` `  `# This code is contributed by Rituraj Jain `

## C#

 `// C# implementation of the approach ` `using` `System; ` ` `  `class` `GFG { ` ` `  `    ``// Function that checks if ` `    ``// the String contain exactly ` `    ``// K characters having ASCII ` `    ``// value greater than p ` `    ``bool` `isValidSubString(String r, ``int` `K, ``int` `p) ` `    ``{ ` `        ``int` `c = 0; ` ` `  `        ``for` `(``int` `i = 0; i < r.Length; i++) { ` ` `  `            ``// if ASCII value is ` `            ``// greater than 'p' ` `            ``if` `((``int``)r[i] > p) { ` `                ``c++; ` `            ``} ` `        ``} ` ` `  `        ``// if count of satisfying ` `        ``// characters is equal to 'K' ` `        ``// then return true ` `        ``if` `(c == K) { ` `            ``return` `true``; ` `        ``} ` ` `  `        ``// otherwise return false ` `        ``else` `{ ` `            ``return` `false``; ` `        ``} ` `    ``} ` ` `  `    ``// function to count sub-Strings ` `    ``void` `countSubStrings(String s, ``int` `K, ``int` `p) ` `    ``{ ` `        ``// length of the String ` `        ``int` `l = s.Length; ` ` `  `        ``// count of sub-Strings ` `        ``int` `count = 0; ` ` `  `        ``// 'i' is the starting ` `        ``// index for the sub-String ` `        ``for` `(``int` `i = 0; i < l; i++) { ` ` `  `            ``// 'j' is the no. of characters ` `            ``// to include in the sub-String ` `            ``for` `(``int` `j = K; (i + j) <= l; j++) { ` ` `  `                ``String r = s.Substring(i, j); ` ` `  `                ``// check if the sub-String ` `                ``// satisfies the condition ` `                ``if` `(isValidSubString(r, K, p)) { ` `                    ``count++; ` `                ``} ` `            ``} ` `        ``} ` `        ``Console.WriteLine(count); ` `    ``} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `Main(String[] args) ` `    ``{ ` `        ``GFG g = ``new` `GFG(); ` `        ``String s = ``"abepztydba"``; ` `        ``int` `K = 4; ` `        ``int` `p = 110; ` ` `  `        ``g.countSubStrings(s, K, p); ` `    ``} ` `} ` ` `  `/* This code contributed by PrinciRaj1992 */`

Output:

```16
```

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