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int a[];
a = new int[32];
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int a[];
for(int i=0;i<32;i++)
{
a[i]=new int();
}
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long flag=1;
long sum=0;
for(int i=1 ;i<=11;i++){
flag *=i;
sum +=flag;
}//ÕâÑùËãʱ¼ä¸´ÔÓ¶ÈÖ»ÓÐT(n)=O(n);
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public class Test{
public static long sumFactorial(int f) throws Exception{
long flag=1;
long sum=0;
for(int i=1;i<=f;i++){
flag *=i;
sum +=flag;
if(flag<0)throw new Exception("Òç³öÁË£¡£¡£¡ÔÚµÚ"+i+"¸ö½×³Ë³öÏÖ¸ºÊý");
if(sum<0)throw new Exception("Òç³öÁË£¡£¡£¡ÔÚµÚ"+i+"¸ö½×³ËÖ®ºÍ³öÏÖ¸ºÊý");
}
return sum;
}
public static void main(String [] agrs) throws Exception{
System.out.println(sumFactorial(11));
}
}
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