C Programming Code Examples
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Program to Replace Lowercase Characters by Uppercase & Vice-Versa
/* Program to Replace Lowercase Characters by Uppercase & Vice-Versa
This program accepts the sentence and replaces lowercase characters by uppercase & vice-versa.
1. Take an an English sentence as input and store it in the array sentence[].
2. Copy the last letter's position in the array to the variable count.
3. Using for loop and (islower()? toupper():tolower()) function replace lowercase characters by uppercase & vice-versa. Store this in the variable ch.
4. Print the variable ch as output and exit.
C program to read an English sentence and replace lowercase characters by uppercase and vice-versa. Output the given sentence as well as the converted sentence on two different lines. */
#include <stdio.h>
#include <ctype.h>
void main()
{
char sentence[100];
int count, ch, i;
printf("Enter a sentence \n");
for (i = 0;(sentence[i] = getchar()) != '\n'; i++)
{
;
}
sentence[i] = '\0';
/* shows the number of chars accepted in a sentence */
count = i;
printf("The given sentence is : %s", sentence);
printf("\n Case changed sentence is: ");
for (i = 0; i < count; i++)
{
ch = islower(sentence[i])? toupper(sentence[i]) :
tolower(sentence[i]);
putchar(ch);
}
}
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Convert lowercase letter to uppercase. Converts c to its uppercase equivalent if c is a lowercase letter and has an uppercase equivalent. If no such conversion is possible, the value returned is c unchanged. Notice that what is considered a letter may depend on the locale being used; In the default "C" locale, a lowercase letter is any of: a b c d e f g h i j k l m n o p q r s t u v w x y z, which translate respectively to: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.
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Checks whether c is a lowercase letter. Notice that what is considered a letter may depend on the locale being used; In the default "C" locale, a lowercase letter is any of: a b c d e f g h i j k l m n o p q r s t u v w x y z. Other locales may consider a different selection of characters as lowercase characters, but never characters that returns true for iscntrl, isdigit, ispunct or isspace. For a detailed chart on what the different ctype functions return for each character of the standard ANSII character set, see the reference for the <cctype> header.
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Convert uppercase letter to lowercase. Converts c to its lowercase equivalent if c is an uppercase letter and has a lowercase equivalent. If no such conversion is possible, the value returned is c unchanged. Notice that what is considered a letter may depend on the locale being used; In the default "C" locale, an uppercase letter is any of: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z, which translate respectively to: a b c d e f g h i j k l m n o p q r s t u v w x y z.
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