w3resource

C Programming: Convert a string to uppercase

C String: Exercise-21 with Solution

Write a program in C to convert a string to uppercase.

C Programming: Convert a string to uppercase

Sample Solution:

C Code:

#include<stdio.h>
#include<ctype.h>

int main()
{
	int ctr=0;
	char str_char;
	char str[100]; 
    
	printf("\n Convert a string to uppercase. :\n");  
    printf("-----------------------------------");      
    printf("\n Input a string in lowercase : ");
    fgets(str, sizeof str, stdin);  
    printf(" Here is the above string in UPPERCASE :\n ");
	while (str[ctr])
	{
		str_char=str[ctr];
		putchar (toupper(str_char));
		ctr++;
	}
	printf("\n\n");
	return 0;
}

Sample Output:

 Convert a string to uppercase. :
-----------------------------------
 Input a string in lowercase : the quick brown fox jumps over the lazy dog.
 Here is the above string in UPPERCASE :
 THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG.

Flowchart :

Flowchart: Convert a string to uppercase

C Programming Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a program in C to find the largest and smallest word in a string.
Next: Write a program in C to convert a string to lowercase.

What is the difficulty level of this exercise?



C Programming: Tips of the Day

Is there a way to specify how many characters of a string to print out using printf()?

The basic way is:

printf ("Here are the first 8 chars: %.8s\n", "A string that is more than 8 chars"); 

The other, often more useful, way is:

printf ("Here are the first %d chars: %.*s\n", 8, 8, "A string that is more than 8 chars"); 

Here, you specify the length as an int argument to printf(), which treats the '*' in the format as a request to get the length from an argument.

You can also use the notation:

printf ("Here are the first 8 chars: %*.*s\n",
        8, 8, "A string that is more than 8 chars"); 

This is also analogous to the "%8.8s" notation, but again allows you to specify the minimum and maximum lengths at runtime - more realistically in a scenario like:

printf("Data: %*.*s Other info: %d\n", minlen, maxlen, string, info); 

The POSIX specification for printf() defines these mechanisms.

Ref: https://bit.ly/395Zj2j