ds: 1e: karatsuba prototype

2025-12-15 18:53:54 +03:00
parent 3a425db8b4
commit 9c8d3a7b5f
3 changed files with 227 additions and 24 deletions
--- a/ds/25-1/1e/test.py
+++ b/ds/25-1/1e/test.py
@ -0,0 +1,17 @@
+U8_MAX = 0xFFFFFFFFFFFFFFFF
+U16_MAX = U8_MAX << 64 | U8_MAX
+U32_MAX = U16_MAX << 128 | U16_MAX
+
+def dothex(num):
+    strhex = hex(num)[2:]
+    dothex = strhex[-16:]
+    strhex = strhex[:-16]
+    
+    while len(strhex) > 0:
+        dothex = strhex[-16:] + '.' + dothex
+        strhex = strhex[:-16]
+
+    return '0x' + dothex
+
+print('mul16', dothex(U16_MAX * 2 % (U16_MAX + 1)))
+print('mul32', dothex(U32_MAX * U16_MAX % (U32_MAX + 1)))