# JavaScript: Subtract elements from one another in an array

## JavaScript Math: Exercise-45 with Solution

Write a JavaScript function to subtract elements from an array.

Sample Solution:

JavaScript Code:

``````// Define a function named subtraction that performs subtraction on an array of numbers.
function subtraction(arr)
{
// Check if the input is an array.
if (Object.prototype.toString.call(arr) === '[object Array]') {
// Initialize the total variable with the first element of the array.
var total = arr[0];
// Check if the first element is a number.
if (typeof (total) !== 'number') {
return false;
}
// Iterate through the array starting from the second element.
for (var i = 1, length = arr.length; i < length; i++)
{
// Check if the current element is a number.
if (typeof (arr[i]) === 'number')
{
// Subtract the current element from the total.
total -= arr[i];
}
else
return false;
}
// Return the result of the subtraction.
}
else
return false;
}

// Output the result of subtracting elements in the array [7, 3, 2, -1] to the console.
console.log(subtraction([7,3, 2,-1]));
```
```

Output:

```3
```

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-math-exercise-45 by w3resource (@w3resource) on CodePen.

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