字符串的第一个大写字母(迭代和递归)

给定一个字符串，找到它的第一个大写字母
例子 ：

Input : geeksforgeeKs
Output : K

Input  : geekS
Output : S

方法1：线性搜索
使用线性搜索，找到首个大写字符

C++

// C++ program to find the first
// uppercase letter using linear search
#include 
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

Javascript

      // JavaScript 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 (var i = 0; i < str.length; i++)
          if (str[i] === str[i].toUpperCase()) return str[i];
        return 0;
      }
 
      // Driver code
 
      var str = "geeksforGeeKS";
      var res = first(str);
      if (res == 0) document.write("No uppercase letter");
      else {
        document.write(res);
        document.write("<br>");
      }
       
      // This code is contributed by rdtank.
    

输出：

G

方法2(使用递归)
递归遍历字符串，如果找到任何大写字母，则返回该字符

C++

// C++ program to find the
// first uppercase letter.
#include 
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.

的Python 3

def capital(N, i, x):
    if i >= x:
        return -1
    elif N[i].isupper():
        return i
    if i < x:
        return capital(N, i + 1, x)
 
 
def main():
    N = input()
    N = list(N)
    x = len(N)
    y = (capital(N, 0, x))
    print(y)
 
 
if __name__ == '__main__':
    main()

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.

输出 ：

G