Menu

Tech

English

Checked Updates

Part of the Fundamentals section of Coddy's Solidity journey. Lesson 50 of 53.

Challenge

Medium

Declare state variable value and event Changed(uint256 value). Require nextValue to be at most 100, assign it to value, emit Changed(value), then print value. Tests use valid values; retain the guard for invalid calls.

The tests pass arguments to main in this order: uint256 nextValue. Each test starts with fresh contract state.

Use console.log for the requested output. Print only the requested values, one per line, with no extra labels unless the task specifies them.

Try it yourself

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.26;
import "forge-std/console.sol";
contract Main {
    function main(uint256 nextValue) external  {
        // Write your solution here.
    }
}

All lessons in Fundamentals

1Introduction

Solidity Hello World!Comments Basic Program Structure

4Decisions

Comparisons Logical Operators If and Else Else If Chains Entry Rules

7Loops

For Loops While Loops Running Totals Break and Continue Even Number Total

10Contract Rules

Require Conditions Explicit Reverts Events Visibility and PrivacyChecked Updates

2Variables and Types

Unsigned Integers Inputs and Output Signed Integers Boolean Values Strings in Memory Profile Card

5Functions

Function Parameters Returning Values Pure Functions Helper Calls Reusable Calculations

8Arrays

Fixed-Size Arrays Dynamic Memory Arrays Storage Arrays Looping Through Arrays Array Summary

11Final Challenges

Inventory Tracker Score Board Reservation Summary

3Arithmetic

Addition and Subtraction Multiplication Integer Division Remainders Packing Orders

6Contract State

State Variables Reading and Writing State Public State Getters Constants Shared Counter

9Data Models

Addresses Mappings Structs Enums Member Records

Practice on your own: Solidity playground