1=2;;
`a`=`b`;;
1=2 or 1<2;;
1<>2 || not 1=2;;
1=1 && 2=2;;
1=1 & 2=2;;
3+5;;
3*5;;
3.*.5.;;
3/5;;
1073741824+1;;
exp(1.)+.exp(-1.);;
3.*.0.5;;
'a';;
`a`;;
"bonjour" ^ "les enfants";;
hd [1,2,3];;
[|1;`a`; 1a |];;
[|1;2;3|];;
0::[|1;2;3|];;
[|1;3;4|].(0);;



hd [1;2;3];;
tl [1;2;4;5;2;3];;
[1;2;3].(2);;

let x=1 in 2+x;;
let x=1;;
x;;
2*x where x=3;;
let (x,y)=(1,2) in x+y;;
let x=1 and y=2 in x+y;;
let f1= function x->x*x;;
f1(3);;

let f2= fun x->x*x;;
f2(2);;

let f3 x=x*x;;
f3 3;;

let p1(x,y)=x*y;;
p1(2, 4);;

let p2 x y=x*y;;
p2(3, 4);;

let p3=function(x,y)->x*y;;
p3(2, 4);;

let x=1;;
let f=fun y->x+y;; f(2);;

let x=ref(0);;
x:=!x+1;;
x;;

(*Exercice 3*)
log(2.71);;

exp(2.)*.log(3.)/.(cos(1.)*.cos(1.));;

let ch = function x->(exp(x)+.exp(-1.*.x))/.2.;;
ch(1.);;



(*Exerice 4*)
let P1 = (1=1);;
let P2 = (2=2);;

let xor = fun x y-> (x || y) && not (y && x);;

let xor2 = function(x, y)-> (x || y) && not (y && x);;

xor P1 P2;;
xor2 (P1, P2);;
(P1 || P2) && not (P1 && P2);;

(*Exercice 5*)
let rec ari a r n = if n = 0 then a else (ari a r (n-1)) + r;;

ari 0 2 3;;