strupr() function in c

The strupr( ) function is used to converts a given string to uppercase. 

Syntax:

char *strupr(char *str);

Parameter:

• str: This represents the given string which we want to convert into uppercase.

Returns: It returns the modified string obtained after converting the characters of the given string str to uppercase.

Time Complexity: O(n)

Auxiliary Space: O(1)

 Below programs illustrate the strupr() function in C: 

Example 1:-

c

// c program to demonstrate
// example of strupr() function.
#include<stdio.h>
#include<string.h>

int main()
{
    char str[ ] = "geeksforgeeks is the best";
    //converting the given string into uppercase.
    printf("%s\n", strupr (str));
    return 0;
}

Output:

GEEKSFORGEEKS IS THE BEST

Example 2:-

c

// c program to demonstrate
// example of strupr() function.

#include<stdio.h>
#include <string.h>

int main()
{
char str[] = "CompuTer ScienCe PoRTAl fOr geeKS";

printf("Given string is: %s\n", str);

printf("\nstring after converting to the uppercase is: %s", strupr(str));
return 0;
}

Output:

Given string is: CompuTer ScienCe PoRTAl fOr geeKS

string after converting to the uppercase is: COMPUTER SCIENCE PORTAL FOR GEEKS

Note : This is a non-standard function that works only with older versions of Microsoft C.