diff --git a/recherche_de_carre/board.js b/recherche_de_carre/board.js
new file mode 100644
index 0000000..bc73853
--- /dev/null
+++ b/recherche_de_carre/board.js
@@ -0,0 +1,279 @@
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// fonctions utilitaires
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+
+function min(a,b) {
+ return a<b ? a : b;
+}
+
+function col_to_str(col,the_board) {
+ var col_str="";
+ for(var i_lines=0;i_lines<the_board.rows.length;i_lines++) {
+ col_str+=the_board.rows[i_lines][col];
+ }
+ return col_str;
+}
+
+function set_char_at(index,chr,str) {
+ if(index > str.length-1) return str;
+ return str.substring(0,index) + chr + str.substring(index+1);
+}
+
+function get_random_char(str) {
+ return str[Math.floor(Math.random() * str.length)];
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// fonctions métier
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+// génération d'un board aléttoire
+function generate_board(rows,cols) {
+ var occurences = "...............o.";
+ var board={rows:[]};
+ for(i=0;i<cols;i++) {
+ str = "";
+ for(j=0;j<rows;j++) {
+ str += get_random_char(occurences);
+ }
+ board.rows[i]=str;
+ }
+ return board;
+}
+
+
+// chercher la plus grande distance possible avant un o ou la fin de la chaine / la valeur d'arrêt
+function get_distance_to_blocking_o(start,stop,str) {
+ //console.log("get_distance_to_blocking_o",start,stop,str);
+ //start+stop-1, -1 parce que le char est compté dans la la dimension du stop
+ var last_char_to_check = (stop < 0 ? str.length : min(start+stop-1,str.length));
+ //var tmp_str=set_char_at(start,"|",str);
+ //var tmp_str2=set_char_at(last_char_to_check-1,"|",tmp_str);
+ //console.log("get_distance_to_blocking_o",start,last_char_to_check,tmp_str2);
+
+ for(var i_char=start;i_char<last_char_to_check;i_char++) {
+ if(str[i_char]=="o") {
+ return(i_char-start);
+ }
+ }
+ return(last_char_to_check-start);
+}
+
+// chercher le plus grand carré possible depuis un point (vers le bas / la droite)
+function get_biggest_square_on_board_at(row,col,the_board,current_max_width=-1) {
+ // console.log("starting at ",row,col,current_max_width);
+ // si il n'y a pas de ligne row, ou pas de colonne col, on renvoie 0
+ if(row >= the_board.rows.length || col >= the_board.rows[0].length) {
+ // console.log("out of bounds");
+ return 0;
+ }
+ // si on est sur un o on renvoie 0
+ if(the_board.rows[row][col] == "o") {
+ // console.log("got an o");
+ return 0;
+ }
+ // on commence en se disant qu'on peut faire tout le reste du board en partant de notre position
+ // on cherche à la position actuelle jusqu'ou on peut aller en longeur et en largeur
+ // la longeur max est jusqu'au premier o qu'on trouve
+ var max_width = get_distance_to_blocking_o(col,current_max_width,the_board.rows[row]);
+ // console.log("max w",max_width);
+ // la hauter maximum est jusqu'au premier o qu'on trouve, pas besoin de chercher plus loin que la largeur max
+ // console.log("col : ",col," => ",col_to_str(col,the_board));
+ var max_height = get_distance_to_blocking_o(row,current_max_width,col_to_str(col,the_board));
+ // console.log("max h",max_height);
+ // la dimension max est le min des deux.
+ current_max_width = min(max_width,max_height);
+ // console.log(max_width,",",max_height, "=>",current_max_width);
+ // si c'est plus de 1, c'est à dire le plus petit carré possible, alors
+ // la dimension max est donc 1 + la dimension max de ce quon peut faire en descendant en diagonale dans le sous carré
+ if(current_max_width > 1) {
+ return 1 + get_biggest_square_on_board_at(row+1,col+1,the_board,current_max_width);
+ }
+ // sinon on est est soit à la fin de ce qu'on peut chercher (dimensions du tableau ou on est tombé sur un o)
+ return current_max_width;
+}
+
+// chercher le plus grand carré possible pour une ligne
+function get_biggest_square_for_row(row,the_board) {
+ var biggest_for_row = {width:0};
+ var current_width = 0;
+ for(var i_col=0;i_col<the_board.rows[row].length;i_col++) {
+ current_width = get_biggest_square_on_board_at(row,i_col,the_board);
+ // console.log("at row ",row,", col ",i_col," => ",current_width);
+ if(current_width > biggest_for_row.width) {
+ biggest_for_row.row = row;
+ biggest_for_row.col = i_col;
+ biggest_for_row.width = current_width;
+ }
+ }
+ return biggest_for_row;
+}
+
+//chercher le plus grand carré pour un tableau
+function get_biggest_square_for_board(the_board) {
+ var biggest_in_board_for_now = {width:0};
+ //console.log("biggest : ",biggest);
+ for(var i_row=0; i_row<the_board.rows.length; i_row++) {
+ current_square = get_biggest_square_for_row(i_row,the_board);
+ if(current_square.width > biggest_in_board_for_now.width) {
+ biggest_in_board_for_now = current_square;
+ }
+ }
+ return(biggest_in_board_for_now);
+}
+
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// déclarations de tableaux
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+board1 = {
+ rows: [
+ ".....o..........",
+ ".....o.....o....",
+ "................",
+ "....o...........",
+ "..........o.....",
+ "................",
+ "....o...o.......",
+ "................",
+ ".............o.."
+ ]
+}
+
+board2 = {
+ rows: [
+ "o....o..........",
+ "...........o....",
+ "................",
+ "....o...........",
+ "..........o.....",
+ "................",
+ "....o...o.......",
+ "................",
+ ".............o.."
+ ]
+}
+
+
+board3 = {
+ rows: [
+ "................",
+ "................",
+ "................",
+ "................",
+ "................",
+ "................",
+ "................",
+ "................",
+ "................"
+ ]
+}
+
+board4 = {
+ rows: [
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo"
+ ]
+}
+
+board5 = {
+ rows: [
+ "................",
+ "................",
+ "................",
+ ]
+}
+
+board6 = {
+ rows: [
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ "oooooooooooooooo",
+ ]
+}
+
+board7 = {
+ rows: [
+ "o....o..........",
+ "...........o....",
+ "................",
+ "....o...........",
+ "..........o.....",
+ "................",
+ "....o...o.......",
+ "................",
+ "................",
+ "................",
+ "................",
+ ".............o.."
+ ]
+}
+
+board8 = {
+ rows: [
+ "o....o.........................",
+ "..........................o....",
+ "..............o................",
+ "....o........ooo...............",
+ "..............o..........o.....",
+ "...............o...............",
+ "....o..................o.......",
+ "o..............................",
+ "...............................",
+ ".....................o.........",
+ ".....................o.........",
+ ".....................o.........",
+ ".........ooo...................",
+ "................o..............",
+ "..................o............",
+ "....................o..........",
+ "...............................",
+ "............................o.."
+ ]
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// TESTS
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+// console.log('board1 0,0 ',get_biggest_square_on_board_at(0,0,board1));
+// console.log('board2 0,0 ',get_biggest_square_on_board_at(0,0,board2));
+// console.log('board3 0,0 ',get_biggest_square_on_board_at(0,0,board3));
+// console.log('board4 0,0 ',get_biggest_square_on_board_at(0,0,board4));
+// console.log('board5 0,0 ',get_biggest_square_on_board_at(0,0,board5));
+// console.log('board6 0,0 ',get_biggest_square_on_board_at(0,0,board6));
+// console.log('board1 5,0 ',get_biggest_square_on_board_at(5,0,board1));
+// console.log('board1 0,5 ',get_biggest_square_on_board_at(0,5,board1));
+// console.log('board1 6,0 ',get_biggest_square_on_board_at(6,0,board1));
+// console.log('board1 0,6 ',get_biggest_square_on_board_at(0,6,board1));
+//console.log('board1 1,12 ',get_biggest_square_on_board_at(1,12,board1));
+//console.log(get_distance_to_blocking_o(12,-1,"...........o...."));
+//console.log('board1 1,6 ',get_biggest_square_on_board_at(1,6,board1));
+//console.log('board1 1,12 ',get_biggest_square_on_board_at(1,12,board1));
+//console.log('board1 1,5 ',get_biggest_square_on_board_at(1,5,board1));
+//console.log('board1 0 ',get_biggest_square_for_row(0,board1));
+//console.log('board2 0 ',get_biggest_square_for_row(0,board2));
+//console.log('board3 0 ',get_biggest_square_for_row(0,board3));
+//console.log('board4 0 ',get_biggest_square_for_row(0,board4));
+//console.log('board5 0 ',get_biggest_square_for_row(0,board5));
+//console.log('board6 0 ',get_biggest_square_for_row(0,board6));
+//console.log('board1 1 ',get_biggest_square_for_row(1,board1));
+//console.log('board1 1 ',get_biggest_square_for_row(2,board1));
+//console.log('board2 0 ',get_biggest_square_for_row(0,board2));
+
+for(i_board=1;i_board<9;i_board++) {
+ console.log('board'+i_board+' ',eval("board"+i_board),get_biggest_square_for_board(eval("board"+i_board)));
+}
+
+var new_board = generate_board(100,100);
+console.log("generated_board ",new_board,get_biggest_square_for_board(new_board));
\ No newline at end of file