Refs #454 -- Added Uint to general/build/smart-contracts/gas-optimization

docs/general/build/smart-contracts/gas-optimization/constant.md

@@ -1,9 +1,9 @@
 ---
 displayed_sidebar: generalSidebar
-sidebar_position: 1
 
 ---
 
+
 # Constant vs Immutable
 
 1. `constant`: Declares a constant that must be initialized at the time of declaration and cannot be altered thereafter.

docs/general/build/smart-contracts/gas-optimization/uint.md

@@ -0,0 +1,81 @@
+---
+displayed_sidebar: generalSidebar
+---
+
+# Uint Types Gas Comparison
+
+It's a common belief that in Solidity, smaller integer types like `uint8`, `uint16`, `uint32`, `uint64`, `uint128`, and `uint256` might save gas due to their smaller size. However, this isn't always the case.
+
+The Ethereum Virtual Machine (EVM) allocates a 256-bit slot for each stored variable. For instance, if we declare a variable of type `uint8`, the EVM fills the missing bits with zeros to fit it into a single slot. Additionally, during execution, the EVM converts `uintN` types to `uint256` for computations.
+
+**DemoCode**
+
+Let's test `uint8`, `uint32`, and `uint256` to observe their behavior in terms of writing data.
+
+```solidity
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.13;
+
+contract Uint8Example {
+    uint8 public uint8val;
+
+    // gas 22234
+    function set() external {
+        uint8val = 1;
+    }
+
+    // gas 53427
+    function compute() external returns (uint8) {
+        uint8 target = 50;
+        for (uint8 i = 0; i < target; i++) {
+            uint8val += 1;
+        }
+        return uint8val;
+    }
+}
+
+contract Uint32Example {
+
+    uint32 public uint32val;
+
+    // gas 22234
+    function set() external {
+        uint32val = 1;
+    }
+
+    // gas 53895
+    function compute() external returns (uint32) {
+        uint32 target = 50;
+        for (uint32 i = 0; i < target; i++) {
+            uint32val += 1;
+        }
+        return uint32val;
+    }
+}
+
+contract Uint256Example {
+    uint256 public uint256val;
+
+    // gas 22238
+    function set() external {
+        uint256val = 1;
+    }
+
+    // gas 42950
+    function compute() external returns (uint256) {
+        uint256 target = 50;
+        for (uint256 i = 0; i < target; i++) {
+            uint256val += 1;
+        }
+        return uint256val;
+    }
+}
+
+
+```
+
+As observed, in loop computations, `uint256` saves over 10,000 gas. Therefore, smaller variables don't necessarily equate to gas savings.
+
+Recommendations for gas optimization:
+
+🌟If variables cannot be packed together, using `uint` or `uint256` is the optimal choice.