- C++ Programming Examples
- C++ Programming Examples
- C++: Hello World
- C++: Get Input
- C++: Print Integer
- C++: Add two numbers
- C++: Add, Sub, Multiply, Div
- C++: Add Digits
- C++: Find Average and Percentage
- C++: Find Arithmetic Mean
- C++: Sum of n Natural Numbers
- C++: Sum of n Numbers
- C++: Square's Area and Perimeter
- C++: Rectangle's Area and Perimeter
- C++: Triangle's Area and Perimeter
- C++: Area and Circumference
- C++: Find Simple Interest
- C++: Fahrenheit to Celsius
- C++: Celsius to Fahrenheit
- C++: Print Prime Numbers
- C++: Reverse a Number
- C++: Swap Two Numbers
- C++: Print Multiplication Table
- C++: Find Factorial of a Number
- C++: Find Factors of a Number
- C++: Find HCF and LCM
- C++: Create a Calculator
- C++: Count Digits in a Number
- C++: First and Last Digit Sum
- C++: Product of Number Digits
- C++: Sum of Squares of Digits
- C++: Interchange Digits of Number
- C++ if-else Programs
- C++: Check Even or Odd
- C++: Check Prime or Not
- C++: Check Alphabet or Not
- C++: Check Vowel or Not
- C++: Check Leap Year or Not
- C++: Check Reverse equals Original
- C++: Check Perfect Number
- C++: Check Palindrome or Not
- C++: Check Armstrong or Not
- C++: Divisibility Test
- C++: Find Labor Wage
- C++: Find Discounted Price
- C++: Find Shipping Charge
- C++: Find Telephone Bills
- C++: Calculate Student Grade
- C++: Largest of Two Numbers
- C++: Largest of Three Numbers
- C++ Number Conversion
- C++: Decimal to Binary
- C++: Decimal to Octal
- C++: Decimal to Hexadecimal
- C++: Binary to Decimal
- C++: Binary to Octal
- C++: Binary to Hexadecimal
- C++: Octal to Decimal
- C++: Octal to Binary
- C++: Octal to Hexadecimal
- C++: Hexadecimal to Decimal
- C++: Hexadecimal to Binary
- C++: Hexadecimal to Octal
- C++ Pattern Programs
- C++: Pattern Programs
- C++: Print Diamond Pattern
- C++: Print Floyd's Triangle
- C++: Print Pascal's Triangle
- C++ Array Programs
- C++: 1D Array Program
- C++: Linear Search
- C++: Binary Search
- C++: Largest Element in an Array
- C++: Smallest Element in an Array
- C++: Find Second Largest Element
- C++: Find Second Smallest Element
- C++: Sum of All Elements
- C++: Multiply All Elements
- C++: Element in Even Position
- C++: Element in Odd Position
- C++: Print Even Numbers in Array
- C++: Print Odd Numbers in Array
- C++: Count Even or Odd Numbers
- C++: Sum of Even or Odd Numbers
- C++: Count Positive, Negative, Zero
- C++: Reverse an Array
- C++: Insert an Element
- C++: Delete an Element
- C++: Merge two Arrays
- C++: Bubble Sort
- C++: Selection Sort
- C++: Insertion Sort
- C++: Common Elements
- C++: 2D Array Programs
- C++: Add Two Matrices
- C++: Subtract Two Matrices
- C++: Transpose Matrix
- C++: Multiply Two Matrices
- C++: 3D Array Programs
- C++ String Programs
- C++: Print String
- C++: Find String Length
- C++: Compare Two Strings
- C++: Copy String
- C++: String Concatenation
- C++: Reverse a String
- C++: Delete Vowels from a String
- C++: Delete a Word from a String
- C++: Count Characters in a String
- C++: Count Words in a String
- C++: Frequency of Words
- C++: Remove Spaces from Strings
- C++: Sort a String
- C++: Uppercase to Lowercase
- C++: Lowercase to Uppercase
- C++: Swap Two Strings
- C++: Check the Anagram or Not
- C++: Capitalize All Words in a String
- C++: Get Numbers from a String
- C++ File Programs
- C++: Read a File
- C++: Write Content to a File
- C++: Append Data to a File
- C++: Read and Display File
- C++: Copy a File
- C++: Merge Two Files
- Count Characters in a File
- C++: Capitalize Every Word
- C++: List Files in Directory
- C++: Delete a File
- C++: Encrypt and Decrypt a File
- C++ Misc Programs
- C++: Print ASCII Value
- C++: Add Binary Numbers
- C++: Generate Random Numbers
- C++: Print a Smiling Face
- C++: Days into Years and Months
- C++: Add Two Numbers using Pointer
- C++: Print Fibonacci Series
- C++: Generate Armstrong Numbers
- C++: Find nCr and nPr
- C++: Get IP Address
- C++: Print Date and Time
- C++: Shutdown and Restart Computer
- C++ Programming Tutorial
- C++ Tutorial
C++ program to convert lowercase to uppercase
In this article, you will learn and get code on lowercase to uppercase conversion of both characters and strings in C++. The program is created with and without using library functions. Here is the list of programs available:
- Lowercase Character to Uppercase Conversion without using the Library Function
- Without using the Library Function strupr(), convert a lowercase string to an uppercase string
- Using the library function strupr(), convert lowercase to uppercase
Note: Here, lowercase and uppercase characters actually mean lowercase and uppercase alphabet characters, respectively.
Lowercase Character
An alphabet character written in a small letter, say "c," is called a lowercase alphabet character. The ASCII values of all the 26 lowercase letters (a–z) are 97–122. That is, the ASCII value of a is 97, b is 98, c is 99, and so on.
Uppercase Character
An alphabet character written in capital letters, say C, is called an uppercase alphabet. The ASCII values of all the 26 uppercase letters (A–Z) are 65–90. That is, the ASCII value of A is 65, B is 66, C is 67, and so on.
Lowercase and Uppercase String
If all alphabet characters in a string are written in small letters, then the string can be called a "lowercase string." For example, fresherearth. Whereas, if all the alphabetic characters of a string are written in capital letters, then the string can be called an "uppercase string." fresherearth, for example.
C++ Lowercase character to uppercase
Let's create a program that receives an alphabet character (in lowercase) from the user at run-time. Now convert and print the equivalent uppercase value of the given (entered) character (in lowercase) without using the library function.
The question is: write a program in C++ that converts lowercase characters entered by the user to their equivalent uppercase characters. Here is the answer to this question:
#include<iostream> using namespace std; int main() { char chLower, chUpper; int ascii; cout<<"Enter the Character: "; cin>>chLower; ascii = chLower; ascii = ascii-32; chUpper = ascii; cout<<"\nUppercase: "<<chUpper; cout<<endl; return 0; }
This program was built and runs under the Code::Blocks IDE. Here is its sample run:
Now supply character input (in lowercase), say "c," and press the ENTER key to see its equivalent value in uppercase, as shown in the snapshot given below:
From the above program, the statement:
ascii = chLower;
The ASCII value of the character stored in chLower was set to ascii. Because chLower is of a char (character) type variable, whereas ascii is an int (integer) type variable, the ASCII value (integer) of chLower gets initialized to ascii.
For example, if the user enters c as a lowercase alphabet character input, then c gets stored in chLower and its ASCII value of 99 gets initialized to ascii.
Note: Because the ASCII value of the capital letter "A" is 65, where the ASCII value of the small letter "a" is 97. The difference between both ASCII values is 32. Therefore, subtracting 32 from the ASCII value of a lowercase alphabet character gives you the ASCII value of the equivalent alphabet character in uppercase.
So the statement,
ascii = ascii-32;
initializes ascii-32, 99-32, or 67 to ascii. So the new value of ascii is 67. And 67 is the ASCII value of the capital letter "C."
Therefore, the statement given below:
chUpper = ascii;
initializes the character value whose ASCII value is 67. That will be C. As a result, chUpper = C. Now print the value of chUpper.
What if the user enters an invalid input?
To deal with an invalid input received at runtime by the user, such as:
- a number
- a special character
- or an uppercase character
Then, here is another program to deal with these types of inputs:
#include<iostream> using namespace std; int main() { char chLower, chUpper; int ascii; cout<<"Enter the Character: "; cin>>chLower; if(chLower>='a' && chLower<='z') { ascii = chLower; ascii = ascii-32; chUpper = ascii; cout<<endl<<chLower<<" in Uppercase: "<<chUpper; } else if(chLower>='A' && chLower<='Z') cout<<"\nAlready in Uppercase"; else cout<<"\nInvalid Input!"; cout<<endl; return 0; }
Here is its sample run with user input d:
Here is another sample run with user input D:
And here is the last sample run with user input 3:
C++ Lowercase string to uppercase
Now let's convert the lowercase string received by the user to its equivalent uppercase string. Because string is a combination of characters, we have to convert all the characters (available in string) one by one to uppercase, as shown in the program given below:
#include<iostream> #include<stdio.h> using namespace std; int main() { char strLower[50], strUpper[50]; int ascii, i=0, chk=0; cout<<"Enter the String: "; gets(strLower); while(strLower[i]!='\0') { if(strLower[i]>='a' && strLower[i]<='z') { ascii = strLower[i]; ascii = ascii-32; strUpper[i] = ascii; chk++; } else strUpper[i] = strLower[i]; i++; } strUpper[i]='\0'; if(chk==0) cout<<"\nString is already in Uppercase"; else cout<<"\nUppercase of String: "<<strUpper; cout<<endl; return 0; }
Here is its sample run with user input This is fresherearth:
In C++, use the Library Function strupr() to convert lowercase to uppercase
This is the last program that uses the library function strupr(). The function takes a string as its argument and converts it into its equivalent uppercase string. The function is defined in the string.h header file.
#include<iostream> #include<stdio.h> #include<string.h> using namespace std; int main() { char str[50]; cout<<"Enter the String: "; gets(str); cout<<"\nUppercase of String: "<<strupr(str); cout<<endl; return 0; }
This program produces the same output as the previous one.
The same program in different languages
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