diff --git a/lab3/zad1/include/DHSetup.hpp b/lab3/zad1/include/DHSetup.hpp
index d31f437..217e06d 100644
--- a/lab3/zad1/include/DHSetup.hpp
+++ b/lab3/zad1/include/DHSetup.hpp
@@ -54,11 +54,11 @@ public:
         this->generator = T(num);
     }
 
-    T getGenerator() {
+    T getGenerator() const {
         return generator;
     }
 
-    T power(T a, uint64_t b) {
+    T power(T a, uint64_t b) const {
         T res = 1;
         while (b > 0) {
             if (b % 2 == 1) {
diff --git a/lab3/zad1/include/User.hpp b/lab3/zad1/include/User.hpp
index 88f4d3b..9cf3957 100644
--- a/lab3/zad1/include/User.hpp
+++ b/lab3/zad1/include/User.hpp
@@ -23,7 +23,7 @@ public:
         this->dh = dh;
     }
 
-    T getPublicKey() {
+    T getPublicKey() const {
         return this->dh.power(dh.getGenerator(), this->secret);
     }
 
@@ -31,14 +31,14 @@ public:
         this->key = this->dh.power(a, this->secret);
     }
 
-    T encrypt(T m) {
+    T encrypt(T m) const {
         if (this->key == T(0)) {
             throw std::logic_error("key must be set before encrypting");
         }
         return m * this->key;
     }
 
-    T decrypt(T c) {
+    T decrypt(T c) const {
         if (this->key == T(0)) {
             throw std::logic_error("key must be set before decrypting");
         }