diff --git a/Scarb.toml b/Scarb.toml
index d60f88b..b4d7134 100644
--- a/Scarb.toml
+++ b/Scarb.toml
@@ -14,3 +14,5 @@ snforge_std = { git = "https://github.com/foundry-rs/starknet-foundry", tag = "v
 [[target.starknet-contract]]
 sierra = true
 
+[scripts]
+test = "snforge test"
\ No newline at end of file
diff --git a/assignments/solutions/solutions_3.md b/assignments/solutions/solutions_3.md
new file mode 100644
index 0000000..0bd05a2
--- /dev/null
+++ b/assignments/solutions/solutions_3.md
@@ -0,0 +1,13 @@
+### Counter Details
+
+```
+CounterV2: 
+class_hash: 0x3a609dd24a6ecef2d8614e4885d9b7923c9db38d83fb9a0134ecfbcc1df8ada
+contract: 0x3a07a1e0e8baf948c19b719996fb22dd7d42c5f53dc347c255f81e865885fed
+```
+
+```
+CounterV3: 
+class_hash: 0x55152fc1bda27047634c9ca4a3b8a1a8001e8ce1a042337b399df66bf02caf4
+contract: 0xd7e5df67691fdbddc8ac1719361ac9e50f50f28eab0255a8b35caa9db29a85
+```
\ No newline at end of file
diff --git a/snfoundry.toml b/snfoundry.toml
new file mode 100644
index 0000000..a2df463
--- /dev/null
+++ b/snfoundry.toml
@@ -0,0 +1,9 @@
+# Visit https://foundry-rs.github.io/starknet-foundry/appendix/snfoundry-toml.html for more information
+
+[sncast.stark1]                                    # Define a profile name
+url = "https://free-rpc.nethermind.io/sepolia-juno/"                         # Url of the RPC provider
+accounts_file = "~/.starknet_accounts/starknet_open_zeppelin_accounts.json"                      # Path to the file with the account data
+account = "stark1"                                   # Account from `accounts_file` or default account file that will be used for the transactions
+# keystore = "~/keystore"                                # Path to the keystore file
+# wait_params = { timeout = 500, retry_interval = 10 }   # Wait for submitted transaction parameters
+block_explorer = "StarkScan"                           # Block explorer service used to display links to transaction details
diff --git a/src/counterV2.cairo b/src/counterV2.cairo
new file mode 100644
index 0000000..386efb0
--- /dev/null
+++ b/src/counterV2.cairo
@@ -0,0 +1,55 @@
+#[starknet::interface]
+trait ICounterV2<TContractState> {
+    fn get_count(self: @TContractState) -> u32;
+    fn set_count(ref self: TContractState, amount: u32);
+
+    fn increment(ref self: TContractState);
+    fn decrement(ref self: TContractState);
+}
+
+
+#[starknet::contract]
+mod CounterV2 {
+    use starknet::storage::StoragePointerWriteAccess;
+    use starknet::storage::StoragePointerReadAccess;
+    use starknet::get_caller_address;
+    use starknet::ContractAddress;
+
+    #[storage]
+    struct Storage {
+        owner: ContractAddress,
+        count: u32
+    }
+
+    #[constructor]
+    fn constructor(ref self: ContractState) {
+        self.owner.write(get_caller_address());
+        self.count.write(0);
+    }
+
+    #[abi(embed_v0)]
+    impl CounterV2Impl of super::ICounterV2<ContractState> {
+        fn get_count(self: @ContractState) -> u32 {
+            self.count.read()
+        }
+
+        fn set_count(ref self: ContractState, amount: u32) {
+            if amount != 0 {
+                self.count.write(amount);
+            }
+        }
+
+        fn increment(ref self: ContractState) {
+            self.count.write(self.count.read() + 1);
+        }
+
+        fn decrement(ref self: ContractState) {
+            if self.count.read() == 0 {
+                return;
+            }
+
+            self.count.write(self.count.read() - 1);
+        }
+    }
+}
+
diff --git a/src/counterV3.cairo b/src/counterV3.cairo
new file mode 100644
index 0000000..1ad37cb
--- /dev/null
+++ b/src/counterV3.cairo
@@ -0,0 +1,96 @@
+#[starknet::interface]
+trait ICounterV3<TContractState> {
+    fn get_count(self: @TContractState) -> u32;
+    fn set_count(ref self: TContractState, amount: u32);
+
+    fn increment(ref self: TContractState);
+    fn decrement(ref self: TContractState);
+}
+
+
+#[starknet::contract]
+mod CounterV3 {
+    use starknet::storage::StoragePointerWriteAccess;
+    use starknet::storage::StoragePointerReadAccess;
+    use starknet::get_caller_address;
+    use starknet::{ContractAddress, contract_address_const};
+
+    #[storage]
+    struct Storage {
+        owner: ContractAddress,
+        count: u32
+    }
+
+    #[constructor]
+    fn constructor(ref self: ContractState, _owner: ContractAddress) {
+        self.owner.write(_owner);
+    }
+
+
+    fn set_new_owner(ref self: ContractState, new_owner: ContractAddress) {
+        self.only_owner();
+
+        self.not_address_zero(new_owner);
+
+        self.owner.write(new_owner);
+    }
+
+    #[generate_trait]
+    impl Private of PrivateTrait {
+        fn only_owner(ref self: ContractState) {
+            if get_caller_address() != self.owner.read() {
+                return;
+            }
+        }
+
+        fn not_address_zero(ref self: ContractState, address: ContractAddress) {
+            let zero_address: ContractAddress = contract_address_const();
+
+            if (address == zero_address) {
+                return;
+            }
+        }
+    }
+
+    #[abi(embed_v0)]
+    impl CounterV3Impl of super::ICounterV3<ContractState> {
+        fn get_count(self: @ContractState) -> u32 {
+            self.count.read()
+        }
+
+        // state functions
+
+        fn set_count(ref self: ContractState, amount: u32) {
+            self.only_owner();
+
+            assert(amount <= 50, 'exceeds 50');
+
+            if amount > 50 {
+                return;
+            }
+
+            if amount > 0 {
+                self.count.write(amount);
+            }
+        }
+
+        fn increment(ref self: ContractState) {
+            self.only_owner();
+            if self.count.read() == 50 {
+                return;
+            }
+
+            self.count.write(self.count.read() + 1);
+        }
+
+        fn decrement(ref self: ContractState) {
+            self.only_owner();
+            if self.count.read() == 0 {
+                return;
+            }
+
+            self.count.write(self.count.read() - 1);
+        }
+    }
+}
+
diff --git a/src/intro_to_felt.cairo b/src/intro_to_felt.cairo
index d3ca719..cbc929a 100644
--- a/src/intro_to_felt.cairo
+++ b/src/intro_to_felt.cairo
@@ -5,4 +5,4 @@ pub fn run() -> felt252 {
     let x = 'SAY GM!';
     println!("x value here: {}", x);
     x
-}
\ No newline at end of file
+}
diff --git a/src/is_even.cairo b/src/is_even.cairo
index 254be75..cb580b1 100644
--- a/src/is_even.cairo
+++ b/src/is_even.cairo
@@ -3,7 +3,7 @@ pub fn run(x: u8, y: u8) -> bool {
     let mymod = sum_u8::run(x, y) % 2;
     if mymod == 0 {
         true
-     } else {
-         false
-     }
-}
\ No newline at end of file
+    } else {
+        false
+    }
+}
diff --git a/src/is_odd.cairo b/src/is_odd.cairo
index 5f6638f..5fa3851 100644
--- a/src/is_odd.cairo
+++ b/src/is_odd.cairo
@@ -1,8 +1,8 @@
 pub fn run(x: u8) -> bool {
     let mut mymod = x % 2;
     if mymod != 0 {
-       true
+        true
     } else {
         false
     }
-}
\ No newline at end of file
+}
diff --git a/src/lib.cairo b/src/lib.cairo
index 6670f9f..7c289bc 100644
--- a/src/lib.cairo
+++ b/src/lib.cairo
@@ -5,6 +5,10 @@ mod intro_to_bytearray;
 mod is_odd;
 pub mod utils;
 
+mod counterV2;
+mod counterV3;
+
+
 fn main() {
     intro_to_felt::run();
     intro_to_u8::run(5, 5);
diff --git a/src/utils.cairo b/src/utils.cairo
index cf4285f..773b0d5 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -10,4 +10,4 @@ pub fn high_to_low(x: u16) -> u8 {
 
 pub fn sum_u8(x: u8, y: u8) -> u8 {
     x + y
-}
\ No newline at end of file
+}