CodingDojo-Challenges created by ValentynaGorbachenko - https://repl.it/C3o9/1

CodingDojo-Challenges.js

/*
Get 1 to 255
Write a function that returns an array with all the numbers from 1 to 255. You may use the push() function for this exercise.
*/
function get_array() {
    var arr = [];
    //your code here 
    for(var i=1; i<256; i++){
        arr.push(i);
    }
    return arr; 
}
/*
Get even 1000
Write a function that would get the sum of all the even numbers from 1 to 1000. You may use a modulus operator for this exercise.
*/
function sum_even_numbers(){
    var sum = 0;
    //your code here
    var i=1;
    while(i<=1000){
        if(i%2===0){
            sum = sum+i;
        }
        i++;
    }
    return sum; 
}
/*
Sum odd 5000
Write a function that returns the sum of all the odd numbers from 1 to 5000. (e.g. 1+3+5+...+4997+4999)
*/
function sum_odd_5000() {
    var sum = 0;
    //your code here 
    var i=1
    while(i<=5000){
        if(i%2===1){
            sum = sum+i;
        }
        i++;
    }
    return sum; 
}
/*
Iterate an array
Write a function that returns the sum of all the values within an array. (e.g. [1,2,5] returns 8, [-5,2,5,12] returns 14)
*/
function iterArr(arr) {
    //your code here 
    var sum = 0;
    for(var i=0; i<arr.length; i++){
        sum += arr[i];
    }
    return sum;
}
/*
Find max
Given an array with multiple values, write a function that returns the maximum number in the array. (e.g. for [-3,3,5,7] max is 7)
*/
function findMax(arr) {
    //your code here 
    var max = Math.max.apply(null, arr);
    return max; 
    /*or for loop
    var max = arr[0];
    for(var i=1;i<arr.length;i++){
        if (max < arr[i]){
            max = arr[i];
        }
    }
    return max;
    */
}

/*
Find average
Given an array with multiple values, write a function that returns the average of the values in the array. (e.g. for [1,3,5,7,20] average is 7.2)
*/
function findAvg(arr) {
    //your code here 
    var avg;
    var sum=0;
    arr.forEach(function(elem){
        sum += elem;
    });
    avg = sum/arr.length;
    return avg; 
}

/*
Array odd
Write a function that would return an array of all the odd numbers between 1 to 50. (ex. [1,3,5, .... , 47,49]). Hint: Use 'push' method.
*/
function oddNumbers() {
    var arr = [];
    //your code here 
    var i=1;
    while(i<=50){
        if(i%2===1){
            arr.push(i);
        }
        i++;
    }
    return arr; 
}
/*
Greater than Y
Given value of Y, write a function that takes an array and returns the number of values that are greater than Y. For example if arr = [1, 3, 5, 7] and Y = 3, your function will return 2. (There are two values in the array greater than 3, which are 5, 7).
*/
function greaterY(arr, Y) {
    //your code here 
    var count=0;
    arr.forEach(function(elem){
        if (elem>Y){
            count++;
        }
    });
    return count; 
}
/*
Squares
Given an array with multiple values, write a function that replaces each value in the array with the product of the original value squared by itself. (e.g. [1,5,10,-2] will become [1,25,100,4])
*/
//forEach
function squareVal(arr) {
    //your code here 
    arr.forEach(function(elem,i, arr){
        arr[i] = elem*elem;
    });
    return arr; 
}
//map
function squareVal1(arr) {
    //your code here 
   var arr1 = arr.map(function(val){
        return val*val;
    });
    return arr1; 
}
/*
Negatives
Given an array with multiple values, write a function that replaces any negative numbers within the array with the value of 0. When the program is done the array should contain no negative values. (e.g. [1,5,10,-2] will become [1,5,10,0])
*/
function noNeg(arr) {
    //your code here 
    var noneg = arr.map(function(elem){
        if (elem<0){
            elem = 0;
        }
        return elem;
    });
    return noneg; 
}
/*
Max/Min/Avg
Given an array with multiple values, write a function that returns a new array that only contains the maximum, minimum, and average values of the original array. (e.g. [1,5,10,-2] will return [10,-2,3.5])
*/
function maxMinAvg(arr) {
    //your code here 
    var arrnew=[];
    var sum = 0;
    arr.forEach(function(elem){
        sum += elem;
    });
    arrnew.push(Math.max.apply(null,arr));
    arrnew.push(Math.min.apply(null,arr));
    arrnew.push(sum/arr.length);
    return arrnew; 
}
maxMinAvg([1,2,8]);
/*
Swap values
Write a function that will swap the first and last values of any given array. The default minimum length of the array is 2. (e.g. [1,5,10,-2] will become [-2,5,10,1]).
*/
function swap(arr) {
    //your code here 
    var arrnew = arr.slice();
    var temp = arrnew[0];
    arrnew[0] = arrnew[arrnew.length-1];
    arrnew[arrnew.length-1] = temp;
    return arrnew; 
}


function numToStr(arr){
	arr = arr.map(function(elem){
		if (elem<0){
			return 'Dojo';
		} else {
			return elem;
		}
	});
	return arr;
}

Max/Min/Avg
Given an array with multiple values, write a function that returns a new array that only contains the maximum, minimum, and average values of the original array. (e.g. [1,5,10,-2] will return [10,-2,3.5])

function maxMinAvg(arr) {
//your code here
var arrnew=[];
var sum = 0;
arr.forEach(function(elem){
sum += elem;
});
arrnew.push(Math.max.apply(null,arr));
arrnew.push(Math.min.apply(null,arr));
arrnew.push(sum/arr.length);
return arrnew;
}