Uppercase and lowercase letters

Write a program that reads a letter and prints it in lowercase if it was uppercase, or prints it in uppercase if it was lowercase.

Input : Input consists of a letter.

Output : Print a line with the given letter in lowercase if it was uppercase, or in uppercase if it was lowercase.

#include <iostream>
using namespace std;

int main () {
    char c, nueva;
    cin >> c;
    if (c>='a' and c<='z') nueva= c-32;
    else nueva = c+32;
    cout << nueva << endl;
}