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JavaScript

/**
 * Решето Эрастофена
 **/
/*function ReshetoErastofena(n) {
    var arr = [];
    for (var i = 2; i <= n; i++) {
        arr.push(i);
    }
    for (i = 0; i < arr.length; i++) {
        var x  = arr[i],
            d = arr[i],
            k  = 1,
            index = -1;
        while (x <= arr[arr.length - 1]) {
            x = x + d;
            index = arr.indexOf(x);
            if (index >= 0) {
                arr.splice(index, 1);
                //console.log(arr);
            }
        }
    }
    return arr;
}

console.log(ReshetoErastofena(100));
*/

/*
function getMaxSubSum(arr) {
    var sub_arr = [];
    var maxSum = 0;
    for (i = 0; i < arr.length; i++) {
        var sumFixedStart = 0;
        for(var j = i; j < arr.length; j++) {
            sumFixedStart += arr[j];
            maxSum = Math.max(maxSum, sumFixedStart);
        }
    }
    return maxSum;
}

alert( getMaxSubSum([-1, 2, 3, -9]) ); // 5
alert( getMaxSubSum([-1, 2, 3, -9, 11]) ); // 11
alert( getMaxSubSum([-2, -1, 1, 2]) ); // 3
alert( getMaxSubSum([1, 2, 3]) ); // 6
alert( getMaxSubSum([100, -9, 2, -3, 5]) ); // 100
*/

/*
function unique(arr) {
    var unique_arr = [];
    for (var i = 0; i < arr.length; i++) {
        var is_unique = true;
        for (var j = 0; j < unique_arr.length; j++) {
            if (arr[i] == unique_arr[j]) {
                is_unique = false;
                break;
            }
        }
        if (is_unique) unique_arr.push(arr[i]);
        console.log(unique_arr);
    }
    return unique_arr;
}
var strings = ["кришна", "кришна", "харе", "харе",
  "харе", "харе", "кришна", "кришна", "8-()"];
alert(unique(strings));
*/
/*
var obj = {
    className: 'open menu'
}

function addClass(obj, cls) {
    var cls_arr = [];
    cls_arr = obj.className.split(' ');
    if (cls_arr.indexOf(cls) == -1) {
        cls_arr.push(cls);
    }
    obj.className = cls_arr.join(' ');
}

addClass(obj, 'new'); // obj.className='open menu new'
addClass(obj, 'open');  // без...