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diff --git a/2024/aoc2024-d04.py b/2024/aoc2024-d04.py
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+#advent of code 2024
+#day 04
+#the issue with 1st version of part 2 was that I didn't account for
+#a cross of words "MAM" and "SAS"
+#counting the letters gave a false positive (number of "m" and "s" was the same
+#but it wasn't a cross of 2 "MAS" words
+#now it check independently each word (dirs1 and dirs2)
+
+part1 = 0;
+part2 = 0;
+word = "XMAS";
+dirs = ((1,0),(-1,0),(0,-1),(0,1),(-1,-1),(-1,1),(1,1),(1,-1));
+Alist = [];
+grid = {};
+xm = 0;
+ym = 0;
+
+f = open("04.in","r")
+for y,l in enumerate(f):
+	ym = y +1;
+	l = l[:-1];
+	for x,c in enumerate(l):
+		xm = x +1;
+		grid[(x,y)] = c;
+f.close();
+
+for y in range(ym):
+	for x in range(xm):
+		if grid[(x,y)] == "A": Alist.append((x,y));
+		for d in dirs:
+			dx, dy = d;
+			IsWord = True;
+			for i in range(len(word)):
+				nx = x + dx*i;
+				ny = y + dy*i;
+				nc = grid.get((nx,ny),"q");
+				if nc != word[i]:
+					IsWord = False;
+					break;
+			if IsWord: part1 += 1;
+
+dirs1 = ((-1,-1),(1,1));
+dirs2 = ((-1,1),(1,-1));
+dirs0 = [dirs1,dirs2];
+for A in Alist:
+	x,y = A;
+	xcount = 0;
+	for d0 in dirs0:
+		cross = {};
+		for d in d0:
+			dx,dy = d;
+			nx = x + dx;
+			ny = y + dy;
+			c = grid.get((nx,ny),"q");
+			v = cross.get(c,0);
+			cross[c] = v + 1;
+		if cross.get("S",0) == 1 and cross.get("M",0) ==1:
+			xcount += 1;
+	if xcount == 2: part2 += 1;
+
+print("part 1 =", part1);
+print("part 2 =", part2);