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Solution to the problem-
function checkPrime(n){
for (let i=2; i<=n/2; i++){
if(n%i==0){
return false;
}
}
return true;
}
function checkSemiPrime(number) {
let divisors=[];
for (let i = 2; i * i <= number; ++i){
if (number % i == 0) {
divisors.push(i);
if (i != number / i) divisors.push(number / i);
}
}
let isPrime=true;
if(divisors.length){
for (let j = 0; j < divisors.length; ++j){
if(!checkPrime(divisors[j])){
isPrime=false
break;
}
}
}
if(isPrime && divisors.length){
return true;
}
return false;
}
function semiPrimeCount(n) {
let counter=0;
for (let i = 4; i < n; ++i){
if(checkSemiPrime(i)){
counter++;
}
}
console.log('count',counter)
return counter;
}
semiPrimeCount(10);
// Leave this so we can test your code:
module.exports = semiPrimeCount;
1 Like
function semiPrimeCount(n) {
let res=;
let doublon=true;
let z=null;
for (let x=2;x<n;x++) {
if(primenumber(x)){
for (let y=2;y<n;y++) {
if(primenumber(y)) {
z=x*y;
doublon=res.some(a => a==z);
if(doublon==false && z < n) res.push(z);
}
}
}
}
return res.length;
}
function primenumber(x){
if(x < 2) return false;
for (let i = 2; i <= Math.sqrt(x); i++) {
if (x % i == 0) return false;
}
return true;
}
semiPrimeCount(10);
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
// pArray represents possible prime numbers
const pArray = [];
//Get prime Numers and put in pArray
for (let i=2; i<n; i++) {
//number to be divided by
let isPrime = true;
for (let j=Math.ceil(i/2); j>1; j--) {
if (i === j) {
continue;
} else if (i%j === 0) {
isPrime = false;
break;
}
}
if (isPrime) {
if (!pArray.includes(i)) {
pArray.push(i);
}
}
}
// Calculate and count semiPrimes
let count = 0;
let semiPrimes = [];
for (let x= 4; x<n; x++) {
//y is index of pArray
for (let y = 0; y < pArray.length; y++) {
let semiPrime = false;
if (!semiPrime) {
// z is other index of pArray to multiply by y
for (let z = 0; z<pArray.length; z++) {
if ((pArray[z] * pArray[y] === x) && !semiPrimes.includes(x)) {
semiPrimes.push(x)
count++;
semiPrime = true;
break;
}
}
}
}
}
console.log(count);
return count;
}
semiPrimeCount(10);
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
let primeList = [];
for (let num = 2; num <= n; num++) {
let isPrime = true;
for (let i = 2; i < num; i++) {
if (num % i === 0) {
isPrime = false;
}
}
if (isPrime === true) {
primeList.push(num);
}
}
let semiPrimeList = [];
for (let j = 0; j < primeList.length; j++) {
for (let k = 0; k < primeList.length; k++) {
let semiPrimes = primeList[j] * primeList[k]
if (semiPrimes < n && !semiPrimeList.includes(semiPrimes)) {
semiPrimeList.push(semiPrimes)
}
}
}
console.log(semiPrimeList)
return semiPrimeList.length;
}
console.log(semiPrimeCount(10));
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
const checkIsPrime = (num => {
for (let i = 2; i < num; i++)
if (num % i === 0) return false
return num > 1
})
const getPrimeNumbers = (number) => {
let list = []
for (let i = 1; i < number; i++) {
if (checkIsPrime(i)) list.push(i)
}
return list
}
const nums = getPrimeNumbers(n)
let result = new Set()
for (let n1 of nums)
for (let n2 of nums) {
const r = n1 * n2
if (r < n)
result.add(r)
}
return result.size
}
semiPrimeCount(10);
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
const primes = [];
for (var i = 2; i < n/2; i++) {
if (isPrime(i)) {
primes.push(i);
}
}
let count = 0;
for (var i = 0; i < primes.length; i++) {
for (var j = i; j < primes.length; j++) {
if (primes[i] * primes[j] < n) {
count++;
} else {
break;
}
}
}
return count;
}
function isPrime(n) {
for (var i = 2; i <= n/2; i++) {
if (n % i === 0) return false;
}
return true;
}
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
function primeFinder(n) {
let primes = []
for (let i=2; i<= n ; i++){
let count = 0
for (let j=2; j<=i; j++){
if (i%j===0) {
count++
}
}
if (count>1) {
count=0
} else {
primes.push(i)
count=0
}
}
return primes
}
let primes = primeFinder(n)
let semiPrimes = []
primes.forEach((p,ind,a) => {
primes.forEach((e)=>{
if ((p*e<n)&&(!semiPrimes.includes(p*e))) { semiPrimes.push(p*e)}
})
})
return semiPrimes.length;
}
semiPrimeCount(10);
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
let [products,a0,a1,i]=[[],[],[],2]
while(i<n/2){
a1.push(i);
i++;
}
a1.forEach(no=>{
let factors =[];
let j=1;
while(j<=no){
if(no%j===0){factors.push(j)}
j++;
}
if(factors.length===2){a0.push(no);}
})
a0.forEach((pri,ind)=>{
while(ind<a0.length&&pri*a0[ind]<n){
products.push(pri*a0[ind]);
ind++;
}
});
return products.length
}
function semiPrimeCount(n) {
let primeNumbers = [2, 3];
let semiPrime = [];
const isPrime = (p) => {
if(p ===2 && p===3) return true;
for(let i = 0; i<primeNumbers.length; i++){
if(p % primeNumbers[i] === 0){
return false;
}
}
return true;
}
const isSemiPrime = (p) => {
for(let i = 0; i<primeNumbers.length; i++){
const rem = p % primeNumbers[i];
const q = p / primeNumbers[i];
if(rem === 0 && primeNumbers.includes(q)){
return true;
}
}
return false;
}
if(n < 4){
return [];
}
for( let num = 4; num < n; num ++){
if(isPrime(num)){
primeNumbers.push(num);
}else if(isSemiPrime(num)){
semiPrime.push(num)
}
}
return semiPrime.length;
}
semiPrimeCount(10);
function semiPrimeCount(n) {
const primes =
const semiPrimes =
for(let i=1; i<=n; i++){
if(isPrime(i)){
primes.push(i)
}
}
return isSemiPrime(primes,n)
}
function isSemiPrime(arr, n){
const semiPrimes =
for(let i=1; i<n; i++){
for(let j=0; j < arr.length; j++){
if(i % arr[j] === 0 && i !==arr[j] && isPrime(i / arr[j])){
semiPrimes.push(i)
}
}
}
let uniqueElem = […new Set(semiPrimes)]
return uniqueElem.length
}
function isPrime(num){
if(num === 1){
return false
}
for(let i=2; i<num; i++){
if(num % i === 0){
return false
}
}
return true
}
console.log(semiPrimeCount(10));
// Leave this so we can test your code:
module.exports = semiPrimeCount;
function semiPrimeCount(n) {
if (n < 3) return 0;
const primes = [];
const semiPrimes = new Set();
label: for (let i = 2; i < n / 2; i++) {
for (let j = 2; j <= Math.sqrt(i); j++) {
if (i % j === 0) continue label;
}
primes.push(i);
for (let prime of primes) {
const mult = prime * i;
if (mult > n - 1) break;
semiPrimes.add(mult);
}
}
return semiPrimes.size;
}
