codeforces

236-a.js

// http://codeforces.com/contest/236/problem/A
function judge(str) {
    var arr = str.split('');
    var obj = {};
    var len = 0;

    for (var i = 0; i < arr.length; i++) {
        if (!obj[arr[i]]) {
            obj[arr[i]] = 1;
            len ++;
        }
    }

    if (len % 2) {
        print('IGNORE HIM!');
    } else {
        print('CHAT WITH HER!');
    }

}

judge(readline().split(' ')[0]);

236-b.js

// http://codeforces.com/contest/236/problem/B

var memObj = {};
function d(n) {
    var num = 0;
    if (memObj[n]) {
        num = memObj[n];
    } else {
        if (n == 1) return 1;
        num = 2;
        var k = Math.floor(Math.sqrt(n));
        for (var i = 2; i <= k; i++) {
            if (n%i === 0) {
                num += 2;
            }

            if (i*i ==n ) num --;
        }
        memObj[n] = num;
    }

    return num;
}

function getSum(a,b,c) {
    var sum = 0;
    for (var i = 1; i <= a; i++) {
        for (var j = 1; j <= b; j++) {
            for (var k =1; k <= c; k++) {
                sum += d(i*j*k);
            }
        }
    }

    return sum;
}

var args = readline().split(' ');
print(getSum(args[0], args[1], args[2])%1073741824);

236-c.js

// http://codeforces.com/contest/236/problem/C

function mlcm(n) {
    var res,tmp;
    if (n < 3) {
        return n;
    }

    if (n%2 === 1) {
        res = bigIntMultiply(bigIntMultiply(n, n-1), n-2);
    } else {
        res = bigIntMultiply(bigIntMultiply(n-1, n-2), n-3);

        tmp = 0;
        if (n%3 !== 0) {
            tmp = bigIntMultiply(bigIntMultiply(n, n-1), n-3);
        }

        // not str compare, so use substraction
        res = res - tmp > 0 ? res : tmp;
    }

    return res;
}

// big int number multiply
function bigIntMultiply(f, s) {
    f = f + '';
    s = s + '';

    var fArr = f.split('').reverse();
    var sArr = s.split('').reverse();

    var sumArr = [];
    var fl = fArr.length,
        sl = sArr.length;
    for (var i = 0; i < fl; i++) {
        var carry = 0,
            sum = 0;
        var fi = fArr[i];

        for (var j = 0; j < sl; j++) {
            var sj = sArr[j];

            sum = fi * sj;
            carry = Math.floor(sum / 10);
            sum = sum % 10;
            index = i + j;
            
            if (sumArr[index]) {
                sum += sumArr[index];
                carry += Math.floor(sum/10);
                sum = sum % 10;
                sumArr[index] = sum;
                if (carry > 0) {
                    sumArr = addCarry(sumArr, carry, index + 1);
                }
            } else {
                sumArr[index] = sum;
                if (carry > 0) {
                    sumArr = addCarry(sumArr, carry, index + 1);
                }
            }
        }
    }

    return sumArr.reverse().join('');
}

// add carry number
function addCarry(sumArr, carry, destIndex) {
    var destNum = sumArr[destIndex];
    if (typeof destNum == 'undefined') {
        sumArr.push(carry);
    } else {
        destNum = destNum + carry;
        carry = Math.floor(destNum / 10);
        if (carry > 0) {
            sumArr[destIndex] = destNum % 10;
            sumArr = addCarry(sumArr, carry, destIndex + 1);
        } else {
            sumArr[destIndex] = destNum;
        }
    }

    return sumArr;
}

// console.log(bigIntMultiply(12,12));
// console.log(bigIntMultiply(2,2));
// console.log(bigIntMultiply(8,8));
// console.log(mlcm(9));
// console.log(mlcm(4));
var args = readline().split(' ');
print(mlcm(args[0]));

README.md

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