2021: day3p1

2021/03/part1

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+gamma = 0
+epsilon = 0
+
+with open('input') as f:
+    total = 0
+    g_counts = [0,0,0,0,0,0,0,0,0,0,0,0]
+    e_counts = [0,0,0,0,0,0,0,0,0,0,0,0]
+
+    for line in f:
+        total += 1
+        for idx, chr in enumerate(line[0:12]):
+            if chr == '1':
+                g_counts[idx]+=1
+            else:
+                e_counts[idx]+=1
+
+    target = total / 2
+    for idx, val in enumerate(g_counts):
+        if val > target:
+            gamma += (1 << (11-idx))
+    for idx, val in enumerate(e_counts):
+        if val > target:
+            epsilon += (1 << (11-idx))
+
+print(gamma * epsilon)
+