Vous pouvez supposer que l'entrée doit être entre les lettres minuscules a ~ z
public class Solution {
public static char lowercaseToUppercase(char character) {
character = (char)(character - 32);
return character;
}
public static char uppercaseTolowercase(char character){
character = (char)(character + 32);
return character;
}
public static void main(String [] args){
Scanner sc = new Scanner(System.in);
String str = sc.next();
char character = str.charAt(0);
//Solution so = new Solution();
if(character >= 'a' && character <= 'z'){
System.out.print(lowercaseToUppercase(character));
}
if(character >= 'A' && character <= 'Z'){
System.out.print(uppercaseTolowercase(character));
}
}
}