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let a;
console.log(a);
a = 15;
console.log("Ma variable a = " + a);
let b = 9;
console.log("Ma variable b = " + b);
console.log(`${a} + ${b} = ${a+b}`);
console.log(`${a} - ${b} = ${a-b}`);
console.log(`${a} * ${b} = ${a*b}`);
console.log(`${a} / ${b} = ${a/b}`);
a = 'Bonjour ';
b = 'les amis';
console.log(`${a + b}`);
a = true;
b = false;
console.log(`${a&&b}`);
console.log(`${a||b}`);
a = new Date()
console.log(`${a}`)
b = new Date()
b.setDate(a.getDate() - 61)
console.log(`${b}`)
let date = new Date()
console.log(date.toLocaleString())
console.log(date.toLocaleDateString())
date.setDate(date.getDate() - 61)
console.log(date.toLocaleString())
console.log(date.toLocaleDateString("de-DE"))
a = Math.PI;
b = 'Bonjour';
c = true;
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} est de type ` + typeof d)