bool(true)
Array ( [lundi] => 10 [mardi] => 45 [mercredi] => 72 )
72
Array ( [lundi] => 10 [mardi] => 45 [mercredi] => 72 [jeudi] => 50 ) 
Array
(
    [0] => Array
        (
            [tiroir1] => 1
            [tiroir2] => 4
            [tiroir3] => 7
        )

    [1] => Array
        (
            [tiroir1] => peluche
            [tiroir2] => chaussette
            [tiroir3] => t-shirt
        )

)
tongs
peluche
Array ( [0] => toto [1] => titi [2] => tutu )
Array ( [0] => toto [1] => titi [2] => tutu [3] => rose )
Array ( [0] => tata [1] => tyty [2] => toto [3] => titi [4] => tutu [5] => rose )
Array ( [0] => tata [1] => tyty [2] => toto [3] => titi [4] => tutu )
Array ( [0] => tyty [1] => toto [2] => titi [3] => tutu )
4
1
ne renvoie rien car pas trouvé
2renvoie l'indice ou se trouve l'élément
ne renvoie pas d'indice car l'élément n'est pas dans le tab

Array ( [0] => pomme [1] => banane [2] => orange )
pomme,banane,orange
Array ( [0] => pomme [1] => banane [2] => orange )