process.stdin.resume();
process.stdin.setEncoding('utf8');
var lines = [];
var reader = require('readline').createInterface({
  input: process.stdin,
  output: process.stdout
});
reader.on('line', (line) => {
  lines.push(line);
});
reader.on('close', () => {
var N = lines[0];
var H = lines[1];
var W = lines[2];
var line = N - H + 1;
var row = N - W + 1;
var res = line * row;
  console.log(res);
});