九度OJ---1040

http://ac.jobdu.com/problem.php?pid=1040

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import java.util.Scanner; publicclass Main { publicstatic void main(String[] args) { Scanner sc = new Scanner(System.in); while (sc.hasNext()) { int n = sc.nextInt(); System.out.println(getPrimeNumber(n)); } } publicstatic int getPrimeNumber( int n) { int [] total = newint [ 10000 ]; total[ 0 ] = 2 ; int count = 1 ; for ( int i = 3 ; i <= 200000 ; i++) { boolean flag = true ; int temp = i; for ( int j = 2 ; j <= Math.sqrt(temp); j++) { if (temp % j == 0 ) { flag = false ; break ; } } if (flag) { if (count< 10000 ) total[count++] = i; } } if (n > total.length) return - 1 ; return total[n - 1 ]; } }