Add day 17 solution

day-17/day-17.py

@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+from pathlib import Path
+
+
+def part_1(input):
+    result = 0
+    x, y = input[0].rstrip().replace('target area: ', '').replace(
+        'x=', '').replace('y=', '').split(', ')
+    x_min, x_max = [int(c) for c in x.split('..')]
+    y_min, y_max = [int(c) for c in y.split('..')]
+    vx_0 = 0
+    min_num_steps = 0
+    while True:
+        vx_0 += 1
+        x_end = vx_0 * (vx_0 + 1) / 2
+        if x_min <= x_end <= x_max:
+            min_num_steps = vx_0
+            break
+        elif x_end > x_max:
+            break
+    max_valid_height = 0
+    for vy_0 in range(-y_min):
+        vy = vy_0
+        y_pos = 0
+        max_height = 0
+        while y_pos > y_min:
+            y_pos += vy
+            max_height = max(max_height, y_pos)
+            vy -= 1
+            if y_min <= y_pos <= y_max:
+                max_valid_height = max(max_valid_height, max_height)
+    result = max_valid_height
+    print("Part 1 result:", result)
+
+
+def part_2(input):
+    result = 0
+    x, y = input[0].rstrip().replace('target area: ', '').replace(
+        'x=', '').replace('y=', '').split(', ')
+    x_min, x_max = [int(c) for c in x.split('..')]
+    y_min, y_max = [int(c) for c in y.split('..')]
+    vx_0 = 0
+    num_steps = 0
+    while True:
+        vx_0 += 1
+        x_end = vx_0 * (vx_0 + 1) / 2
+        if x_min <= x_end <= x_max:
+            num_steps = vx_0
+        elif x_end > x_max:
+            break
+    for vx_0 in range(x_max + 1):
+        for vy_0 in range(y_min, -y_min):
+            vx = vx_0
+            vy = vy_0
+            x_pos = 0
+            y_pos = 0
+            while x_pos < x_max and y_pos > y_min:
+                x_pos += vx
+                y_pos += vy
+                if vx != 0:
+                    vx -= 1
+                vy -= 1
+                if x_min <= x_pos <= x_max and \
+                        y_min <= y_pos <= y_max:
+                    result += 1
+                    break
+    print("Part 2 result:", result)
+
+
+input = list()
+p = Path(__file__).with_name('input.txt')
+with open(p) as f:
+    input = f.readlines()
+    part_1(input)
+    part_2(input)