Display alternate character of string in upper case

Write a C program to accept a string and display its alternate character in upper case. (Ex: I/P  hello O/P hElLo).

Solution:

#include<stdio.h>
#include<string.h>
#include<ctype.h>
int main()
{
    char str[30];
    int i;
    printf("Enter String : ");
    gets(str);

    for(i = 0; str[i] != '\0'; i++)
    {
        if( (i % 2) == 0)
            str[i] = tolower(str[i]);
        else
            str[i] = toupper(str[i]);
    }
    printf("\n%s", str);
    return 0;
}


Output:

alternate char uppercase
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