PHP, 22 bytes

<?=array_sum(file(t)); 

This assumes there is a file named "t" with a list of integers.

file() opens a file and returns an array with each line stored as separate elements in the array. array_sum() sums all the elements in an array.

PHP, 22 bytes

<?=array_sum(file(t)); 

This assumes there is a file named "t" with a list of integers.

file() opens a file and returns an array with each line stored a separate element in the array. array_sum() sums all the elements in an array.

PHP, 22 bytes

<?=array_sum(file(t)); 

Assuming a file named "t" with the list of integers

PHP, 22 bytes

<?=array_sum(file(t)); 

This assumes there is a file named "t" with a list of integers.

file() opens a file and returns an array with each line stored as separate elements in the array. array_sum() sums all the elements in an array.