> For the complete documentation index, see [llms.txt](https://edp.ethkipu.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://edp.ethkipu.org/modulo-2/fundamentos-de-solidity/operadores/ejercicio-2.md).

# Ejercicio 2

En este ejercicio haremos unas modificaciones al contrato anterior para poder contar el número de veces que modificamos la variable **`storedInfo` .** Para ello utilizaremos un contador denominado **`countChanges`**que será una variable de tipo uint que debe ser visible de forma pública.

**Pasos a seguir:**

1. Programe el contrato en Remix,
2. Despliéguelo en una red de prueba de Ethereum como Sepolia,
3. Publique y verifique el contrato utilizando un explorador de bloques
4. Interactúe con el contrato a través del explorador de bloques modificando tres veces el valor de **`setInfo`** y verificando que así lo hizo con el contador **`countChanges`**

```solidity
// SPDX-License-Identifier: GPL-3.0
pragma solidity 0.8.19;
 
/// @title Concepts: variable uint with public visibility
/// @author Solange Gueiros
contract ChangeCounter {
    string private storedInfo;
    uint public countChanges = 0;

    /**
    * Store `myInfo`
    * Increase the counter which manage how many times storedInfo is updated
    * @dev stores the string in the state variable `storedInfo` and update the counter
    * @param myInfo the new string to store
    */
    function setInfo(string memory myInfo) external {
        storedInfo = myInfo;
        countChanges++;
    }

    /**
    * Return the stored string
    * @dev retrieves the string of the state variable `storedInfo`
    * @return the stored string
    */
    function getInfo() external view returns (string memory ) {
        return storedInfo;
    }
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://edp.ethkipu.org/modulo-2/fundamentos-de-solidity/operadores/ejercicio-2.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.