Day21 implemented

Author: am93

day21.py

@@ -0,0 +1,46 @@
+def shout(name, val, mb):
+    if name == 'humn' and val >= 0:
+        return val
+    ops = mb[name]
+    if len(ops) == 1:
+        return int(ops[0])
+    else:
+        return eval(''.join(ops).replace(ops[0], str(shout(ops[0], val, mb)))
+                                .replace(ops[2], str(shout(ops[2], val, mb))))
+
+
+mnky_bussiness = {}
+
+for line in open('inputs/day21.txt').readlines():
+    words = line.split()
+    name = words[0].strip(':')
+    mnky_bussiness[name] = line.split(':')[1].split()
+
+print('Part1:', shout('root', -1, mnky_bussiness))
+
+mnky1 = mnky_bussiness['root'][0]
+mnky2 = mnky_bussiness['root'][2]
+
+mnky1_score = shout(mnky1, -1, mnky_bussiness)
+mnky2_score = shout(mnky2, -1, mnky_bussiness)
+
+target = 0
+if mnky1_score < mnky2_score:
+    target = mnky1_score
+    othr_mnky = mnky2
+else:
+    target = mnky2_score
+    othr_mnky = mnky1
+
+bottom = 0
+top = 124765768589550    # my part1 solution -
+while bottom < top:
+    mid = (bottom + top)//2
+    score = target - shout(othr_mnky, mid, mnky_bussiness)
+    if score < 0:
+        bottom = mid
+    elif score == 0:
+        print('Part2:', mid)
+        break
+    else:
+        top = mid