console.clear();
let a;
console.log(a);
a = 15;
console.log("Ma variable a = " + a);
let b = 9;
console.log("Ma variable b = " + b);
console.log("15 + 9 = "+ (a+b));
console.log("15 - 9 = "+ (a-b));
console.log("15 * 9 = "+ (a*b));
console.log("15 / 9 = "+ (a/b));
a = "Bonjour";
b = "les amis";
console.log(a +" "+ b);
a = true;
b = false;
console.log("true AND false = "+ (a && b));
console.log("true OR false = "+ (a || b));
a = new Date()
console.log(a.toLocaleDateString("ch-FR"));
b = new Date(a.getTime() - ((61) * 864000000));
console.log(b.toLocaleDateString("ch-FR"));
a = Math.PI;
b = "bonjour";
let c = true;
let d = new Date();
console.log(a +" est de type "+ (typeof a));
console.log(b +" est de type "+ (typeof b));
console.log(c +" est de type "+ (typeof c));
console.log(d.toLocaleDateString("ch-FR") +" est de type "+ (typeof d));