与えられた数のランタイムファインディング除数を必要とする

Question

現在、HackerRankの問題に対して時間制限の問題を超えています。問題の状態は、与えられた数のすべての奇数除数を合計します。これは私のコードです：

int[] numbers = {21, 11, 7}; 

    long total = 0; 
    for (int i = 0; i < numbers.length; i++) { 
     for (int j = 1; j <= numbers[i]; j+=2) { 
      if (numbers[i] % j == 0) { 
       total += (long) j; 
      } 
     } 
    } 

int []番号は可変であり、何千もの数字を含むことができます。私はどんな助けにも感謝します。

int[] numbers = { 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 
     21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7, 21, 11, 7}; 

Answer 1

最初のsqrt(n)の除数しか見つからないようにコードをスピードアップすることができます。私がNを分けると、N/iも除数の他の部分として得られ、調べる必要がある最大のものはsqrt（n）であることに注意してください。

サンプルコード：

int sum = 0; 
for(int n : all the numbers){ 
    for(int i = 1; i*i<=n;i++){ 
     if(n%i == 0){ 
      if(i % 2 == 1)sum+=i; 
      if((n/i) % 2 == 1)sum += (n/i); 
     } 
    } 
} 
return sum; 

Answer 2

ランタイムを減らす1つの方法は、奇数除数を現在見つけている数の1/2にのみ反復することです。それ以上の数は、その数の約数ではないことができて、あなたはこの中間点を超えてチェックする必要はありません

for (int j = 1; j <= numbers[i]/2; j+=2) { 
    if (numbers[i] % j == 0) { 
     total += (long) j; 
    } 
} 

：それは次のようになります。