What's wrong with this code? I tried get marks using array and pass the array in to function parameters and calculate the average in that function.

const marks = [100,100,80];
var summ = 0;

function calculateGrade(){
    
    for(let i=0; i<=marks.length;i  ){
       
        summ = summ marks[i];
        var avg = (summ/marks.length);  
    }
    
    if(avg<=59){
        console.log('F');
    }
    else if(avg>=60 && avg<=69){
        console.log('D');
    }
    else if(avg>=70 && avg<=79){
        console.log('C');
    }
    else if(avg>=80 && avg<=89){
        console.log('B');
    }
    else if(avg>=90 && avg<=100){
        console.log('A');
    }
}

console.log(calculateGrade(marks));

CodePudding user response：

You are very close

const marks = [100, 100, 80];


function calculateGrade(marks) {

  let summ = 0;

  for (let i = 0; i < marks.length; i  ) {
    summ  = marks[i];
  }
  const avg = summ / marks.length;
  if (avg < 59) {
    console.log('F');
  } else if (avg <= 69) {
    console.log('D');
  } else if (avg <= 79) {
    console.log('C');
  } else if (avg <= 89) {
    console.log('B');
  } else {
    console.log('A');
  }
}

calculateGrade(marks);

CodePudding user response：

You just added an extra = in your for loop

i<=marks.length

instead of

i<marks.length

So while calculating the sum & average, a garbage value gets added up.

CodePudding user response：

 const marks = [100, 100, 80];
  var summ = 0;
   
  //issue one (Tmarks were missing )
  function calculateGrade(Tmarks) {
    // issues 2 ( <= should be < )
    for (let i = 0; i < Tmarks.length; i  ) {
      summ  = Tmarks[i];
    }
    var avg = summ / Tmarks.length;
    if (avg <= 59) {
      console.log("F");
    } else if (avg >= 60 && avg <= 69) {
      console.log("D");
    } else if (avg >= 70 && avg <= 79) {
      console.log("C");
    } else if (avg >= 80 && avg <= 89) {
      console.log("B");
    } else if (avg >= 90 && avg <= 100) {
      console.log("A");
    }
  }

  console.log(calculateGrade(marks));

Following were the issues in your code

1. You were not getting the parameters in function definition
2. issues 2 ( <= should be < )