V2 Cairo counter assignment implementation

DEPLOYMENT_STEPS.md

@@ -0,0 +1,188 @@
+# CounterV2 Deployment Steps
+
+## Step 1: Create The Account Entry
+
+```bash
+sncast account create --name Yusrah --network sepolia
+```
+
+Save the generated account address and fund it with Sepolia tokens for fees.
+
+## Step 2: Deploy The Account
+
+```bash
+sncast account deploy --name Yusrah --network sepolia
+```
+
+## Step 3: List Accounts
+
+```bash
+sncast account list
+```
+
+Save the address for the `Yusrah` account.
+
+Yusrah's acc. address 0x72658e0505e77137829e255912c52f8ca0ae73de5dde8332686b1adac3034f0
+
+## Step 4: Go Into The Contract Package
+
+```bash
+cd ~/Desktop/cairo-begining/cairo-bootcamp-6/starknet_contracts
+```
+
+## Step 5: Build The Contract
+
+```bash
+scarb build
+```
+
+## Step 6: Declare CounterV2
+
+```bash
+sncast --account Yusrah \
+  declare \
+  --contract-name CounterV2 \
+  --network sepolia \
+  --wait
+```
+
+Save the `class_hash` from the output.
+
+class harsh  0x1e3a5b348490a07cea9f2788b81e46132c107724621e462494a5d20b67d458d
+
+## Step 7: Deploy CounterV2
+
+Replace:
+
+- `PASTE_CLASS_HASH_HERE`
+- `PASTE_YUSRAH_ADDRESS_HERE`
+
+```bash
+sncast --account Yusrah \
+  deploy \
+  --class-hash PASTE_CLASS_HASH_HERE \
+  --constructor-calldata PASTE_YUSRAH_ADDRESS_HERE \
+  --network sepolia \
+  --wait
+```
+
+Save the deployed `contract_address`.
+
+contract address 0x031e9847e60b0e7224c095cd45e260aa96daa0cec22960a8ab1cc51949997f36
+
+## Step 8: Verify The Owner
+
+Replace `PASTE_CONTRACT_ADDRESS_HERE`.
+
+```bash
+sncast call \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function get_owner \
+  --network sepolia
+```
+
+## Step 9: Verify The Initial Count
+
+```bash
+sncast call \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function get_count \
+  --network sepolia
+```
+
+Expected:
+
+```text
+0
+```
+
+## Step 10: Increase The Count By 10
+
+```bash
+sncast --account Yusrah \
+  invoke \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function increase_count \
+  --calldata 10 \
+  --network sepolia \
+  --wait
+```
+
+## Step 11: Verify The Count After Increasing
+
+```bash
+sncast call \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function get_count \
+  --network sepolia
+```
+
+Expected:
+
+```text
+10
+```
+
+## Step 12: Reduce The Count By 4
+
+```bash
+sncast --account Yusrah \
+  invoke \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function reduce_count \
+  --calldata 4 \
+  --network sepolia \
+  --wait
+```
+
+## Step 13: Verify The Count After Reducing
+
+```bash
+sncast call \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function get_count \
+  --network sepolia
+```
+
+Expected:
+
+```text
+6
+```
+
+## Step 14: Demo Subtraction Underflow Protection
+
+```bash
+sncast --account Yusrah \
+  invoke \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function reduce_count \
+  --calldata 200 \
+  --network sepolia \
+  --wait
+```
+
+Expected:
+
+An error because the subtraction underflows.
+
+## Step 15: Demo Non-Owner Rejection
+
+Replace `OTHER_ACCOUNT_NAME`.
+
+```bash
+sncast --account OTHER_ACCOUNT_NAME \
+  invoke \
+  --contract-address PASTE_CONTRACT_ADDRESS_HERE \
+  --function increase_count \
+  --calldata 1 \
+  --network sepolia \
+  --wait
+```
+
+Expected:
+
+An error because the caller is not the owner.
+
+
+e.g of non owner address 0x00A879C0fEf9C803041Ab7524859879B5d68684f413890401566367ae38a3a10

README.md

@@ -1,22 +1,54 @@
-# Cairo Bootcamp 6.0
+# Cairo Bootcamp 6 Assignment
 
-Welcome to **Cairo Bootcamp 6** — a hands-on, developer-focused program designed to help you learn Cairo from first principles and build real-world applications. This repository contains learning materials, examples, and exercises used throughout the bootcamp.
+This repo contains my Cairo assignment split into two versions:
 
----
+- `V1`: the earlier simple Starknet counter contract and standalone arithmetic practice
+- `V2`: the improved version where the Starknet contract imports reusable Cairo arithmetic logic and adds access control
 
-## About the Bootcamp
+## Assignment Summary
 
-This Cairo Bootcamp is designed to:
-- Introduce developers to Cairo 
-- Teach provable computation fundamentals**
-- Explore Starknet and smart contract development
-- Encourage hands-on building and experimentation
+The assignment required the following:
 
+- add a subtraction check so negative results throw an error
+- write multiplication and division functions and handle their error cases
+- add `only_owner` to state-changing functions
+- make `increase_count` read the current storage value and add the incoming amount instead of overwriting storage
+- import Cairo arithmetic logic into the Starknet contract for `increase_count` and `reduce_count`
 
----
+## Project Structure
 
-## 📁 Repository Structure
-.
-├── cairo_programs/ # Pure Cairo programs (stateless logic)
-├── starknet_contracts/ # Smart contracts (stateful logic)
-└── README.md
+- `cairo_program/`: plain Cairo logic
+- `starknet_contracts/`: Starknet contracts
+
+## V1 Files
+
+- Cairo arithmetic practice: [cairo_program/src/integer.cairo](cairo_program/src/integer.cairo)
+- Simple Starknet contract: [starknet_contracts/src/counter_v1.cairo](starknet_contracts/src/counter_v1.cairo)
+
+## V2 Files
+
+- Reusable arithmetic logic: [cairo_program/src/arithmetic_v2.cairo](cairo_program/src/arithmetic_v2.cairo)
+- Cairo library export: [cairo_program/src/lib.cairo](cairo_program/src/lib.cairo)
+- Improved Starknet contract: [starknet_contracts/src/counter_v2.cairo](starknet_contracts/src/counter_v2.cairo)
+- Starknet package entry: [starknet_contracts/src/lib.cairo](starknet_contracts/src/lib.cairo)
+
+## What Was Implemented In V2
+
+- `sub_num` checks for underflow and throws an error
+- `mul_num` checks for overflow
+- `div_num` checks for division by zero
+- `increase_count` uses imported addition logic
+- `reduce_count` uses imported subtraction logic
+- `increase_count` reads the current count from storage before updating it
+- `only_owner` restricts state-changing functions
+
+## Build Status
+
+Both packages compile successfully:
+
+- `cairo_program`
+- `starknet_contracts`
+
+## Next Step
+
+The next step after this PR is deployment of `CounterV2`, where the owner address will be passed into the constructor.

cairo_program/README.md

@@ -1,17 +1,26 @@
 # Cairo Program
 
-Welcome to **Cairo Bootcamp 6** — a hands-on, developer-focused program designed to help you learn Cairo from first principles and build real-world applications. This repository contains learning materials, examples, and exercises used throughout the bootcamp.
+This package contains the plain Cairo logic used in the assignment.
 
----
+## Files
 
+- `src/integer.cairo`: V1 arithmetic practice
+- `src/arithmetic_v2.cairo`: V2 reusable arithmetic functions
+- `src/lib.cairo`: exports the V2 arithmetic module for reuse by the Starknet contract package
 
+## V2 Arithmetic
 
----
+The reusable V2 module includes:
 
-## 📁 Repository Structure
-.
-├── src/ 
-├── starknet_contracts/ # Smart contracts (stateful logic)
-├── exercises/ # Practice tasks and assignments
-├── notes/ # Learning notes (felt, syntax, etc.)
-└── README.md
+- `add_num`
+- `sub_num`
+- `mul_num`
+- `div_num`
+
+Error handling included:
+
+- subtraction underflow protection
+- multiplication overflow protection
+- division-by-zero protection
+
+This package is imported into the V2 Starknet contract so the contract can reuse the arithmetic logic instead of doing the arithmetic inline.

cairo_program/Scarb.toml

@@ -5,6 +5,8 @@ edition = "2025_12"
 
 # See more keys and their definitions at https://docs.swmansion.com/scarb/docs/reference/manifest.html
 
+[lib]
+
 [executable]
 
 [cairo]
@@ -13,4 +15,3 @@ enable-gas = false
 [dependencies]
 cairo_execute = "2.18.0"
 
-

cairo_program/src/arithmetic_v2.cairo

@@ -0,0 +1,29 @@
+pub fn add_num(x: u32, y: u32) -> u32 {
+    x + y
+}
+
+pub fn sub_num(x: u32, y: u32) -> u32 {
+    if y > x {
+        panic!("Sub underflow");
+    }
+    x - y
+}
+
+pub fn mul_num(x: u32, y: u32) -> u32 {
+    let wide_x: u64 = x.into();
+    let wide_y: u64 = y.into();
+    let result = wide_x * wide_y;
+
+    if result > 4294967295_u64 {
+        panic!("Mul overflow");
+    }
+
+    result.try_into().unwrap()
+}
+
+pub fn div_num(x: u32, y: u32) -> u32 {
+    if y == 0 {
+        panic!("Cannot divide 0");
+    }
+    x / y
+}

cairo_program/src/bool.cairo

@@ -11,7 +11,7 @@ fn main() {
 fn is_adult(x: u8) -> bool {
     // let mut outcome: bool = false;
     if x <= 18 {
-        // outcome = false;
+   =;/ outcome = false;
         return false;
     }
     // outcome = true;

cairo_program/src/lib.cairo

@@ -2,4 +2,5 @@
 // mod short_string;
 // mod integer;
 // mod bool;
-mod bytearray;
+mod bytearray;
+pub mod arithmetic_v2;

starknet_contracts/Scarb.lock

@@ -1,6 +1,10 @@
 # Code generated by scarb DO NOT EDIT.
 version = 1
 
+[[package]]
+name = "cairo_6"
+version = "0.1.0"
+
 [[package]]
 name = "snforge_scarb_plugin"
 version = "0.56.0"
@@ -20,5 +24,6 @@ dependencies = [
 name = "starknet_contracts"
 version = "0.1.0"
 dependencies = [
+ "cairo_6",
  "snforge_std",
 ]

starknet_contracts/Scarb.toml

@@ -7,6 +7,7 @@ edition = "2024_07"
 
 [dependencies]
 starknet = "2.18.0"
+cairo_6 = { path = "../cairo_program" }
 
 [dev-dependencies]
 snforge_std = "0.56.0"