JS实现计算小于非负数n的素数的数量算法示例

<script>
 var countPrimes = function(n) {
 let flagArray = [],
 result = 0;
 for(let i = 2; i < n; i++){
 if(flagArray[i] === undefined){
 flagArray[i] = 1;
 result++;
 let j = 2;
 while(i * j < n){// 将以后与当前值能整除的排除掉
 flagArray[i * j] = 0;
 j++;
 }
 }
 }
 return result;
};
console.log(countPrimes(10));
console.log(countPrimes(100));
</script>

<script>
function PrimesList(m,n){
 var rel = [];
 for (var i = m; i < n ; i++) {
 for (var j = 2; j < i; j++) {
 if (i%j==0)
 {
 break;
 }
 else{
 rel.push(i);
 }
 }
 }
 return rel
}
console.log(PrimesList(100,200));
</script>