count_students.js

/*
Alex from Scrimba wants to know how many new students have attended 
Scrimba's weekly Town Hall event this year. 

He has an array of first-time attendees for each month of the year. 
Help him find the total number of attendees! Your function should
take in an array and return a number representing the total number
of new attendees. 

Example input: [1,2,3]
Example output: 6
 */

const studentCount = [50, 53, 61, 67, 60, 70, 78, 80, 80, 81, 90, 110];

// 1ST WAY--> 
// function sumArray(arr){
//     let sum = 0;
//     for(let item of arr){
//         sum += item; // We are using the for...of loop to iterate over the array. The for...of loop iterates over the values in the array, not the indices.
//     }
//     return sum;
// }

// console.log(sumArray(studentCount));

// 2ND WAY--> 
// function sumArray(arr) {
//   let sum = 0;
//  for (let i = 0; i < arr.length; i++) {
//     sum += arr[i];
//   }
//   return sum;
// }

// console.log(sumArray(studentCount));

// 3RD WAY -->
// function sumArray(arr){
//     // initialize a new variable to hold the sum of the arr 
//     let sum = 0;
//     // loop through the studentCount arr, add each value to the sum
//     arr.forEach(item => sum += item);
//     // after done looping, return the sum
//     return sum;
// }

// console.log(sumArray(studentCount));

// 4TH WAY -->
function sumArray(arr) {
  return arr.reduce((sum, item) => sum += item, 0);
}

console.log(sumArray(studentCount));