swap_case

def swap_case(s):
    return s.swapcase()

if __name__ == '__main__':
    s = input()
    result = swap_case(s)
    print(result)

in c programming

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

void swap_case(char *s) {
    for (int i = 0; s[i] != '\0'; i++) {
        if (islower(s[i])) {
            s[i] = toupper(s[i]);
        } else if (isupper(s[i])) {
            s[i] = tolower(s[i]);
        }
    }
}

int main() {
    char s[1000];
    fgets(s, sizeof(s), stdin);
    swap_case(s);
    printf("%s", s);
    return 0;
}


in java programming

   import java.util.Scanner;

public class SwapCase {
    public static String swapCase(String s) {
        StringBuilder result = new StringBuilder();
        for (char c : s.toCharArray()) {
            if (Character.isUpperCase(c)) {
                result.append(Character.toLowerCase(c));
            } else if (Character.isLowerCase(c)) {
                result.append(Character.toUpperCase(c));
            } else {
                result.append(c);
            }
        }
        return result.toString();
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String s = scanner.nextLine();
        System.out.println(swapCase(s));
        scanner.close();
    }
}