Added 2021 (python)

2021/17/input

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+target area: x=29..73, y=-248..-194

2021/17/prog.py

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+import math, re
+VERBOSE = True
+def verbose(s = "", *args, **kwargs):
+    if VERBOSE:
+        print(s, *args, **kwargs)
+
+def get_input(sample = False, part = 1):
+    with open(f'sample_p{part}' if sample else 'input', 'r') as f:
+        m = re.match(r"target area: x=(-?\d+)..(-?\d+), y=(-?\d+)..(-?\d+)", f.readlines()[0])
+        return tuple(map(lambda x: int(x), m.groups()))
+
+
+
+def v_x(t, v0):
+    return max(-t + v0, 0)
+
+def v_y(t, v0):
+    return -t + v0
+
+
+def result(inp, part = 1):
+    y = abs(min(inp[2], inp[3])) - 1
+    v_y_max = int(y*(y+1) / 2);
+    if part == 1:
+        return v_y_max
+
+    x_2 = math.ceil((-1 + math.sqrt(1 - 4 * (-2) * inp[1])) / 2)
+    x_1 = math.ceil((-1 + math.sqrt(1 - 4 * (-2) * inp[0])) / 2)
+    x_min = inp[0]
+    x_max = inp[1]
+    y_min = inp[2]
+    y_max = inp[3]
+
+    global VERBOSE
+
+    res = 0
+    for v0x in range(x_1, x_max+1):
+        for v0y in range(y_min, v_y_max+1):
+            verbose(f"{v0x, v0y}", end = " ")
+            t = 0
+            y = 0
+            x = 0
+            while y >= y_min:
+                y += v_y(t, v0y)
+                x += v_x(t, v0x)
+                # verbose(f"\t{x, y = }")
+                if x_min <= x and x <= x_max and y_min <= y and y <= y_max:
+                    verbose(f"accepted", end='')
+                    res += 1
+                    break
+                t += 1
+            verbose("")
+
+    # x = inp[1] - inp[0]
+    # x += x2 - x1 + 1
+    # verbose(f"{x1, x2 = }")
+    # y = abs(inp[3]) - abs(inp[2])
+    # y +=  v_y_max
+    return res
+
+
+if __name__ == "__main__":
+    VERBOSE = not False
+    print(result(get_input(), part = 2))

2021/17/sample_p1

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+target area: x=20..30, y=-10..-5

2021/17/test.py

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+from prog import *
+import unittest
+
+class Tests(unittest.TestCase):
+    def test_part1(self):
+        self.assertEqual(result(get_input(sample = True)), 45)
+
+    def test_part2(self):
+        self.assertEqual(result(get_input(sample = True), part = 2), 112)
+