first week of AOC 2025

8 files changed, 248 insertions, 2 deletions

diff --git a/2025/2025-d01.py b/2025/2025-d01.py
deleted file mode 100644
index f8c5c0b..0000000
--- a/2025/2025-d01.py
+++ /dev/null
@@ -1,2 +0,0 @@
-#advent of code 2025
-#day 01
diff --git a/2025/aoc2025-d01.py b/2025/aoc2025-d01.py
new file mode 100644
index 0000000..f3e9101
--- /dev/null
+++ b/2025/aoc2025-d01.py
@@ -0,0 +1,20 @@
+#advent of code 2025
+#day 01
+
+dial=50;
+part1=0;
+part2=0;
+bigjumps=0;
+PuzzleInput=open("01.in","r");
+for instruction in PuzzleInput:
+	direction=1*(instruction[0]=="R") -1*(instruction[0]=="L");
+	jump=int(instruction[1:]);
+	for step in range(jump): #yes it's bruteforce
+		dial+=direction;
+		dial=(100+dial)%100;
+		if dial==0: 
+			part2+=1;
+	part1+=dial==0;
+
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d02.py b/2025/aoc2025-d02.py
new file mode 100644
index 0000000..a35e776
--- /dev/null
+++ b/2025/aoc2025-d02.py
@@ -0,0 +1,26 @@
+#advent of code 2025
+#day 02
+
+part1=0;
+part2=0;
+PuzzleInput=open("02.in","r").read();
+for IDrange in PuzzleInput.split(","):
+	IDs=[int(val) for val in IDrange.split("-")];
+	for num in range(IDs[0],IDs[1]+1):
+		strnum=str(num);
+		numlen=len(strnum);
+		half=numlen//2;
+		for step in range(half,0,-1):
+			sublist=[];
+			i=0;
+			while i < numlen:
+				substring=strnum[i:i+step];
+				sublist.append(substring);
+				i+=step;
+			subset=set(sublist);
+			if len(subset)==1 and sublist.count(sublist[0])==len(sublist):
+				if step==half and len(sublist)==2: part1+=num;
+				part2+=num;
+				break;
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d03.py b/2025/aoc2025-d03.py
new file mode 100644
index 0000000..0f315ed
--- /dev/null
+++ b/2025/aoc2025-d03.py
@@ -0,0 +1,25 @@
+#advent of code 2025
+#day 03
+part1=0;
+part2=0;
+
+def joltage(bank,limit):
+	i=0;
+	jolt=0;
+	for bat_ID in range(1-limit,0):
+		battery=max(bank[:bat_ID]);
+		i=bank[:bat_ID].index(battery);
+		bank=bank[i+1:];
+		jolt+=battery*(10**(-bat_ID));
+	jolt+=max(bank);
+	return jolt;
+
+PuzzleInput=open("03.in","r");
+for il,line in enumerate(PuzzleInput):
+	line=line.replace("\n","");
+	bank=[int(c) for c in line];
+	part1+=joltage(bank,2);
+	part2+=joltage(bank,12);
+
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d04.py b/2025/aoc2025-d04.py
new file mode 100644
index 0000000..46e7578
--- /dev/null
+++ b/2025/aoc2025-d04.py
@@ -0,0 +1,31 @@
+#advent of code 2025
+#day 04
+part1=0;
+part2=0;
+wall=set();
+PuzzleInput=open("04.in","r");
+adjacent=[(-1,-1),(0,-1),(1,-1),(-1,0),(1,0),(-1,1),(0,1),(1,1)];
+def IsAccessible(grid,p):
+	neighbors=0;
+	px,py=p;
+	for dx,dy in adjacent:
+		neighbors+=(px+dx,py+dy) in grid;
+	return neighbors<4;
+#parsing
+for y,line in enumerate(PuzzleInput):
+	for x,c in enumerate(line[:-1]):
+		if c=="@": wall.add((x,y));
+PuzzleInput.close();
+#solution
+while True:
+	removed=set();
+	for pos in wall:
+		if IsAccessible(wall,pos):
+			removed.add(pos);
+	if len(removed)==0: break;
+	wall.difference_update(removed);
+	if part1==0: part1+=len(removed);
+	part2+=len(removed);
+#answers
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d05.py b/2025/aoc2025-d05.py
new file mode 100644
index 0000000..5b9c21c
--- /dev/null
+++ b/2025/aoc2025-d05.py
@@ -0,0 +1,36 @@
+#advent of code 2025
+#day 05
+#p1 elementary school tier iterate over list
+#p2 collapse ranges from input: trims it down by ~50%, that's why part 2 runs first
+#lo1 looks a lot like lol
+part1=0;
+part2=0;
+PuzzleInput=open("05.in","r").read().split("\n\n");
+fresh=[ [int(num) for num in nums.split("-") ] for nums in PuzzleInput[0].split("\n")];
+ingredients=[int(food) for food in PuzzleInput[1].split("\n")];
+#part 2
+changes=True;
+while changes:
+	fresh=sorted(fresh);
+	changes=False;
+	for n1,range1 in enumerate(fresh):
+		lo1,hi1=range1;
+		for n2,range2 in enumerate(fresh):
+			if n1==n2: continue;
+			lo2,hi2=range2;
+			if lo1 in range(lo2,hi2+1) or hi1 in range(lo2,hi2+1):
+				fresh[n1]=[min(lo1,lo2),max(hi1,hi2)];
+				fresh.pop(n2);
+				changes=True;
+				break;
+		if changes: break;
+part2=sum([ranHi+1-ranLo for ranLo,ranHi in fresh]);
+#part 1 
+for ingr in ingredients:
+	for lo,hi in fresh:
+		if ingr in range(lo,hi+1):
+			part1+=1;
+			break;
+
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d06.py b/2025/aoc2025-d06.py
new file mode 100644
index 0000000..864cb90
--- /dev/null
+++ b/2025/aoc2025-d06.py
@@ -0,0 +1,54 @@
+#advent of code 2025
+#day 06
+import re
+
+def calculate(values,op):
+	if op=="+":
+		answer=sum(values);
+	elif op=="*":
+		answer=1;
+		for value in values:
+			answer*=value;
+	return answer;
+
+part1=0;
+part2=0;
+PuzzleInput=open("06.in","r");
+problems=dict();
+biggerproblems=dict();
+operators=[];
+for y,line in enumerate(PuzzleInput):
+	line=line.replace("\n","");
+	vals=re.findall(r'(\d+|\*|\+)', line);
+	if y==0: #reserve space for each column
+		for n in range(len(vals)):
+			problems[n]=[];
+		for n in range(len(line)):
+			biggerproblems[n]=[];
+	for x,val in enumerate(vals):
+		problems[x].append(val);
+	if vals.count("+")+vals.count("*")==0:
+		for x,c in enumerate(line):
+			biggerproblems[x].append(c);
+	else:
+		operators=[op for op in vals];
+PuzzleInput.close();
+#part 1
+for n in problems:
+	problems[n]=[[int(num) for num in problems[n][:-1]],problems[n][-1]];
+	part1+=calculate(*problems[n]);
+#part 2
+subproblem=[];
+for n in biggerproblems:
+	problemline=biggerproblems[n];
+	if problemline.count(" ")==len(problemline):
+		operation=operators.pop(0);
+		part2+=calculate(subproblem,operation);
+		subproblem=[];
+		continue;
+	subproblem.append(int("".join(problemline)));
+#last column doesn't have it's own whitespace so it's outside the loop
+operation=operators.pop(0);
+part2+=calculate(subproblem,operation);
+print("part 1",part1);
+print("part 2",part2);
diff --git a/2025/aoc2025-d07.py b/2025/aoc2025-d07.py
new file mode 100644
index 0000000..e72effe
--- /dev/null
+++ b/2025/aoc2025-d07.py
@@ -0,0 +1,56 @@
+#advent of code 2025
+#day 07
+part1=0;
+part2=0;
+#parsing
+grid=dict();
+Ymax=0;
+Xmax=0;
+PuzzleInput=open("07.in","r");
+for y,line in enumerate(PuzzleInput):
+	Ymax+=1;
+	for x,c in enumerate(line.replace("\n","")):
+		grid[(x,y)]=c;
+		Xmax=max(Xmax,x+1);
+		if c=="S":
+			Start=(x,y); 
+			grid[(x,y)]=".";
+PuzzleInput.close();
+#solution
+total=(0,0);
+pathing=dict();
+pathing[total]=set();
+hitBottom=dict();
+splitters=set(); #encountered splitters
+beams=set([(Start,total)]);
+#recursive search
+def findTimelines(point):
+	if point in hitBottom:
+		return hitBottom[point];
+	hitBottom[point]=0;
+	for path in pathing[point]:
+		hitBottom[point]+=findTimelines(path);
+	return hitBottom[point];
+
+for step in range(0,Ymax+1,2): #every 2nd line is empty so i'm skipping it
+	newbeams=set();
+	while beams:
+		b,prev=beams.pop();
+		pathing[prev].add(b);
+		if b not in pathing: pathing[b]=set();
+		bx,by=b;
+		beam=(bx,by+2);
+		if grid.get(beam,".")=="^":
+			splitters.add(beam);
+			newbeams.add(((bx+1,by+2),(bx,by)));
+			newbeams.add(((bx-1,by+2),(bx,by)));
+		else:
+			newbeams.add(((bx,by+2),(bx,by)));
+		if by+2>Ymax and b not in hitBottom: 
+			hitBottom[b]=1; #register from which points beams hit the bottom
+	beams=newbeams;
+
+part1=len(splitters);
+part2=findTimelines(Start);
+print("part 1",part1,part1==1533);
+print("part 2",part2,part2==10733529153890);