diff --git a/number/examples/lpow.cc b/number/examples/lpow.cc
new file mode 100644
index 0000000..42c058f
--- /dev/null
+++ b/number/examples/lpow.cc
@@ -0,0 +1,13 @@
+constexpr int B = 2;
+constexpr int N = 1e5;
+constexpr int s = 31623;  // sqrt(MDL)
+int a[N], b[N];
+
+void prep() {
+    a[0] = b[0] = 1;
+    for(int i = 1; i <= s; i++) a[i] = (ll)a[i - 1] * B % MDL ;
+    for(int i = 1; i <= s; i++) b[i] = (ll)b[i - 1] * a[s] % MDL ;
+}
+
+ll lpow(ll power) { return ll(b[power / s]) * a[power % s] % MDL; }
+