Good afternoon! Here's our prompt for today.

Valid Numeric String

You are working as a software engineer at a company that develops a financial trading platform. Your team is working on a new feature that allows users to enter numeric strings into a text field and have them parsed and converted into numbers.

One of the requirements for this feature is that the numeric strings must be valid. A valid numeric string must consist of:

• A sign character (either + or -).
• One or more digits.
• A decimal point . followed by one or more digits.
• An e or E followed by an integer.

For example, all the following are valid numeric strings:

1"+"
2"-"
3"123"
4"-123.456"
5"1e10"
6"-90E3"

while the following are not valid numeric strings:

1"abc"
2"1a"
3"1e"
4"e3"
5"99e2.5"

You need to write a function that can be used to determine if a given string is a valid numeric string.

Try to solve this here or in Interactive Mode.

How do I practice this challenge?

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// Function where students will fill out the logic

function validNumericString(s) {

  // fill this in

  return;

}

​

// Test cases to validate the function

function runTests() {

  // Test case 1

  const result1 = validNumericString("10.34");

  if (result1 === true) {

    console.log("Test case 1 passed");

  } else {

    console.log("Test case 1 failed");

  }

​

  // Test case 2

  const result2 = validNumericString("10.34e10");

  if (result2 === true) {

    console.log("Test case 2 passed");

  } else {

    console.log("Test case 2 failed");

  }

​

  // Test case 3

  const result3 = validNumericString("10.34.45");

  if (result3 === false) {

    console.log("Test case 3 passed");

  } else {

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