diff --git a/flag_encoder/index.html b/flag_encoder/index.html
index 6f2a92f..37d4e8c 100644
--- a/flag_encoder/index.html
+++ b/flag_encoder/index.html
@@ -25,19 +25,14 @@
 
 		function getPrivateKey() {
 			var s = inpFlag.value;
-			var k = new BN(0);
 			var h = "0x";
 			if (s.slice(0, 5) !== "CCTF{" || s.slice(-1) !== "}")
 				return null;
 			for (i in s) {
 				var c = s.charCodeAt(i);
-				k = k.muln(16).addn(c);
 				h += c.toString(16).padStart(2, "0");
 			}
-			if (k.mod(secp256k1n).eqn(0)) {
-				return null;
-			}
-			return h;
+			return "0x" + new BN(keccak256(h).slice(2), 16).mod(secp256k1n).toString(16).padStart(64, 0);
 		}
 
 		function updateOutputValues(ev) {