48: self powers

48_self_powers/euler48.py

@@ -0,0 +1,17 @@
+def modpow(b, e, m):
+  r = 1
+  while e > 0:
+    if e & 1:
+      r = (r * b) % m
+    b = (b * b) % m
+    e = e >> 1
+  return r
+
+def powersum(n, m):
+  s = 0
+  for i in range(1, n + 1):
+    s+= modpow(i, i, m)
+    s%= m
+  return s
+
+print powersum(1000, 10000000000)