First uppercase letter in a string (Iterative and Recursive)

Given a string find its first uppercase letter

Examples :

Input : geeksforgeeKs
Output : K

Input  : geekS
Output : S

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

Method 1: linear search
Using linear search, find the first character which is capital

C++

// C++ program to find the first 
// uppercase letter using linear search 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to find string which has 
// first character of each word. 
char first(string str) 
{ 
    for (int i = 0; i < str.length(); i++) 
        if (isupper(str[i])) 
            return str[i]; 
    return 0; 
} 
  
// Driver code 
int main() 
{ 
    string str = "geeksforGeeKS"; 
    char res = first(str); 
    if (res == 0) 
        cout << "No uppercase letter"; 
    else
        cout << res << "\n"; 
    return 0; 
} 

Java

// Java program to find the first 
// uppercase letter using linear search 
import java.io.*; 
import java.util.*; 
  
class GFG { 
  
    // Function to find string which has 
    // first character of each word. 
    static char first(String str) 
    { 
        for (int i = 0; i < str.length(); i++) 
            if (Character.isUpperCase(str.charAt(i))) 
                return str.charAt(i); 
        return 0; 
    } 
      
    // Driver program  
    public static void main(String args[]) 
    { 
        String str = "geeksforGeeKS"; 
        char res = first(str); 
        if (res == 0) 
            System.out.println("No uppercase letter"); 
        else
            System.out.println(res); 
    } 
} 
  
  
// This code is contributed 
// by Nikita Tiwari. 

Python3

# Python3 program to find the first 
# uppercase letter using linear search 
  
# Function to find string which has 
# first character of each word. 
def first(str) : 
      
    for i in range(0, len(str)) : 
          
        if (str[i].istitle()) : 
            return str[i] 
              
    return 0
  
  
# Driver code 
str = "geeksforGeeKS"
res = first(str) 
  
if (res == 0) : 
    print("No uppercase letter") 
      
else : 
    print(res) 
      
      
# This code is contributed by Nikita Tiwari 

C#

// C# program to find the first uppercase 
// letter using linear search 
using System; 
  
class GFG { 
      
    // Function to find string which has 
    // first character of each word. 
    static char first(string str) 
    { 
        for (int i = 0; i < str.Length; i++) 
            if (char.IsUpper(str[i]) )  
                return str[i]; 
        return '0'; 
    } 
      
    // Driver function 
    public static void Main() 
    { 
        string str = "geeksforGeeKS"; 
        char res = first(str); 
        if (res == '0') 
            Console.WriteLine("No uppercase" 
                               + " letter"); 
        else
            Console.WriteLine(res); 
    } 
} 
  
// This code is contributed by Sam007 

PHP

<?php 
// PHP program to find the first 
// uppercase letter using linear search 
  
// Function to find string which has 
// first character of each word. 
function first($str) 
{ 
    for ($i = 0; $i < strlen($str); $i++) 
        if (ctype_upper($str[$i])) 
        { 
            return $str[$i]; 
              
        } 
    return 0; 
} 
  
    // Driver code 
    $str = "geeksforGeeKS"; 
    $res = first($str); 
      
    if (ord($res) ==ord(0) ) 
        echo "No uppercase letter"; 
    else
        echo $res . "\n"; 
  
// This code is contributed by Sam007 
?> 

Output:

Method 2 (Using recursion)
Recursively traverse the string and if any uppercase is found return that character

C++

// C++ program to find the 
// first uppercase letter. 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to find string which has 
// first character of each word. 
char first(string str, int i=0) 
{ 
    if (str[i] == '\0') 
         return 0; 
    if (isupper(str[i]))  
            return str[i]; 
    return first(str, i+1); 
} 
  
// Driver code 
int main() 
{ 
    string str = "geeksforGeeKS"; 
    char res = first(str); 
    if (res == 0) 
        cout << "No uppercase letter"; 
    else
        cout << res << "\n"; 
    return 0; 
} 

Java

// Java program to find the 
// first uppercase letter. 
import java.io.*; 
  
class GFG { 
      
    // Function to find string which has 
    // first character of each word. 
    static char first(String str, int i) 
    { 
        if (str.charAt(i) == '\0') 
            return 0; 
        if (Character.isUpperCase(str.charAt(i)))  
                return str.charAt(i); 
        return first(str, i + 1); 
    } 
      
    // Driver code 
    public static void main(String args[]) 
    { 
        String str = "geeksforGeeKS"; 
        char res = first(str,0); 
        if (res == 0) 
            System.out.println("No uppercase letter"); 
        else
            System.out.println (res ); 
    } 
} 
  
// This code is contributed  
// by Nikita Tiwari. 

Python 3

# Python 3 program to find the 
# first uppercase letter. 
#include <bits/stdc++.h> 
  
# Function to find string which has 
# first character of each word. 
def first(str, i): 
  
    if (str[i] == '\0'): 
        return 0
    if (str[i].isupper()): 
        return str[i] 
    return first(str, i+1) 
  
# Driver code 
str = "geeksforGeeKS"
res = first(str,0) 
if (res == 0): 
    print("No uppercase letter") 
else: 
    print(res) 
  
# This code is contributed  
# by Smitha 

C#

// C# program to find the 
// first uppercase letter. 
using System; 
  
class GFG  
{ 
      
    // Function to find string  
    // which has first character 
    // of each word. 
    static char first(string str, int i) 
    { 
        if (str[i] == '\0') 
            return '0'; 
        if (char.IsUpper(str[i])) 
                return (str[i]); 
        return first(str, i + 1); 
    } 
      
    // Driver code 
    static public void Main () 
    { 
        string str = "geeksforGeeKS"; 
        char res = first(str, 0); 
        if (res == 0) 
            Console.WriteLine("No uppercase letter"); 
        else
            Console.WriteLine(res ); 
    } 
} 
  
// This code is contributed by Anuj_67. 

PHP

<?php 
//PHP program to find the 
// first uppercase letter. 
  
// Function to find string  
// which has first character 
// of each word. 
  
function first($str, $i = 0) 
{ 
    if ($str[$i] == '\0') 
        return 0; 
    if (ctype_upper($str[$i]))  
            return $str[$i]; 
    return first($str, $i+1); 
} 
  
// Driver code 
    $str = "geeksforGeeKS"; 
    $res = first($str); 
      
    if (ord($res) ==ord(0)) 
        echo "No uppercase letter"; 
    else
        echo $res , "\n"; 
  
// This code is contributed  
// by m_kit 
?> 

Output :

My Personal Notes

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

C++

Java

Python3

C#

PHP

C++

Java

Python 3

C#

PHP

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