reduce.js

// strings = ["Hello"," ","world","!"];
// //how can you use the reduce() function to concatenate strings in an array
// // const strings = ["Hello", " ", "world", "!"];

// const result = strings.reduce((accumulator, currentValue) => {
//   return accumulator + currentValue;
// });

// console.log(result);


// //let arr = [23,45,66,72,16];
// //arr.reduce(() >= )
// let arr = [
//     {firstname:'rahul',lastname:'jhA',age:25},
//     {firstname:'donald',lastname:'trump',age:76},
//     {firstname:'vikas',lastname:'xyz',age:20},
//     {firstname:'depika',lastname:'paudukone',age:25}
// ];
// //using reduce() to count how many people are of each age
// const ageCount = arr.reduce((acc, person) => {
//     if (acc[person.age]) {
//         acc[person.age]++;
//     } 
//     else {
//         acc[person.age] = 1;
//     }
//     return acc;
// }, {});
// console.log(ageCount);


// print total marks for students with marks greater than 60 after 20 marks have been added to those who scored less than 60.
let students = [
    {name:"smith",rollno:31,marks:80},
    {name:"jenny",rollno:15,marks:69},
    {name:"john",rollno:16,marks:35},
    {name:"tiger",rollno:17,marks:55},
]
let updatedStudents = students.map(students => {
    if (students.marks < 60) {
        students.marks += 20;
    }
    return students;
});
let passedStudents = updatedStudents.filter(student => student.marks > 60);

let totalMarks = passedStudents.reduce((acc, student) => acc + student.marks, 0);

console.log("Total Marks of students with >60:", totalMarks);