Add script is_generator.py

algebre-non-lineaire/is_generator.py

@@ -0,0 +1,35 @@
+#!/usr/bin/env python3
+
+"""In ElGamal cyclic systems, there is at least one generator.
+
+Find out if a given number is a generator.
+"""
+
+def main() -> None:
+    """Ask for p and g and calculate"""
+
+    p = int(input("p: "))
+    g = int(input("g: "))
+
+    print(is_generator(p, g))
+
+
+def is_generator(p: int, g: int) -> bool:
+    """Algorithm"""
+
+    family_size = 0
+
+    for i in range(1, p):
+        total = g ** i % p
+        print(total)
+        if total == 1:
+            family_size = i
+            break
+
+    if family_size == p - 1:
+        return True
+    return False
+
+
+if __name__ == "__main__":
+    main()