# include<iostream.h>
# include<math.h>
# include<stdio.h>


long gcdhelp( long u,long v )
{
	if( u%v == 0 ){
		return v;
	}
	return gcdhelp( v,u%v );
}

long gcd( long u,long v )
{
	if( u > v ){
		return gcdhelp( u,v );
	}
	return gcdhelp( v,u );
}


void main( )
{
	int n;
	while( 1 ){
		cin>>n;
		long count = 0;
		if( n == 0 ){
			break;
		}
		int *a = new int[n];
		for( int i = 0;i < n;i ++ ){
			cin>>a[i];
		}
		for( i = 0;i < n - 1;i ++ ){
			for( int j = i + 1;j < n;j ++ ){
				if( gcd( a[i],a[j] ) == 1 ){
					count ++;
				}
			}
		}
		delete[] a;
		if( count == 0 ){
			cout<<"No estimate for this data set."<<endl;
		}
		else{
			long sum = 3*n*( n - 1 );
			double p = sum/1.0;
			p /= count;
			double pi = sqrt( p );
			printf("%.6f\n",pi);
		}
	}
}

• Re:代码 (0) 8013 2004-02-18 20:08:06
• Re:代码 (17) 00448176 2005-04-27 10:02:07
  • 其实最该改的是"%.6f"，这个东西是对应float而不是对应double的，不过ms很多人喜欢混着用 (58) frkstyc 2005-04-27 10:06:19
    • 原来要用float,害我做了好久。。。。 (41) jackjack 2005-06-26 15:42:24
  • Re:用%.6lf不更保险吗,而且简单 (21) fxlbest 2005-11-15 19:27:39
    • Re:用%.6lf不更保险吗,而且简单 (9) Juwend 2009-05-08 16:00:29