ctx.accounts.counter; counter.count = 0; counter.authority = ctx.accounts.user.key(); msg!("Counter initialized!"); Ok(()) } pub fn greet(_ctx: Context) -> Result<()> { msg!("Hello, Solana!"); Ok(()) } pub fn increment(ctx: Context) -> Result<()> { let counter = &mut ctx.accounts.counter; counter.count += 1; Ok(()) } // TODO: Add a decrement instruction with underflow protection } #[derive(Accounts)] pub struct Initialize<'info> { #[account( init, payer = user, space = 8 + 8 + 32, seeds = [b"counter", user.key().as_ref()], bump )] pub counter: Account<'info, Counter>, #[account(mut)] pub user: Signer<'info>, pub system_program: Program<'info, System>, } #[derive(Accounts)] pub struct Greet {} #[derive(Accounts)] pub struct Increment<'info> { #[account( mut, seeds = [b"counter", user.key().as_ref()], bump )] pub counter: Account<'info, Counter>, pub user: Signer<'info>, } // TODO: Add a Decrement accounts struct (same as Increment) #[account] pub struct Counter { pub count: u64, pub authority: Pubkey, } // TODO: Add a custom ErrorCode enum with Underflow variant 22:T76b,use anchor_lang::prelude::*; declare_id!("Fg6PaFpoGXkYsidMpWTK6W2BeZ7FEfcYkg476zPFsLnS"); #[program] pub mod academy_program { use super::*; pub fn initialize(ctx: Context) -> Result<()> { let counter = &mut ctx.accounts.counter; counter.count = 0; counter.authority = ctx.accounts.user.key(); msg!("Counter initialized!"); Ok(()) } pub fn greet(_ctx: Context) -> Result<()> { msg!("Hello, Solana!"); Ok(()) } pub fn increment(ctx: Context) -> Result<()> { let counter = &mut ctx.accounts.counter; counter.count += 1; Ok(()) } pub fn decrement(ctx: Context) -> Result

Complete Counter Program

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