//Toggle String
// Sample code to perform I/O:

process.stdin.resume();
process.stdin.setEncoding("utf-8");
var stdin_input = "";

process.stdin.on("data", function (input) {
    stdin_input += input;                               // Reading input from STDIN
});

process.stdin.on("end", function () {
   main(stdin_input);
});

function main(input) {
    var data= input.toString().split("\n");

    process.stdout.write(toggle(data[0]));       // Writing output to STDOUT
}

// Warning: Printing unwanted or ill-formatted data to output will cause the test cases to fail



// Write your code here
// Sample code to perform I/O:
//Enter your code here


function toggle(s) {
    var ss="";
    for (var i= 0; i<s.length; i++) {
        
        if (s[i] >= 'a' && s[i] <= 'z') {
           ss= ss+String.fromCharCode(s.charCodeAt(i) - 32);
        } else if (s[i] >= 'A' && s[i] <= 'Z') {
            ss= ss+String.fromCharCode(s.charCodeAt(i) + 32);
         
        }
            
    }    
    return ss;    
}