toj_2948.cpp

Tianjin University Online Judge 的80多道题目 .

#include<cstdio>
#include<cstring>
#include<cmath>
#include<cstdlib>
#define MAXNUM 30

struct Bond
{
    int misson;
    bool ass;
    double p;
};
Bond b[ MAXNUM ][ MAXNUM ];

double max[ MAXNUM ] , maxP;
char choosed[ MAXNUM ];
int choice[ MAXNUM ];

int n;

void findMax( int start , double p )
{
    int i;
    if( p < maxP )
        return;
    if( start == n ){
        if( maxP < p )
            maxP = p;
    }
    else
        for( i = 0; i < n; i++ )
            if( !b[ i ][ start ].ass ){
                b[ i ][ start ].ass = true;
            p *= b[ i ][ start ].p;
            findMax( start + 1 , p );
            b[ i ][ start ].ass = false;
        }
}
        
int main()
{
	int i , j;
	freopen( "toj_2948.in" , "r" , stdin );
	freopen( "toj_2948.out" , "w" , stdout );
	
	while (  scanf( "%d" , &n ) && n != 0 ){
        for( i = 0;i < n; i++ )
            for( j = 0; j < n; j++ ){
                scanf( "%lf" , &b[ i ][ j ].p );
                b[ i ][ j ].p /= 100.0;
                b[ i ][ j ].ass = false;
                b[ i ][ j ].misson = j;
            }
        maxP = -1;
        findMax( 0 , 1.0 );
        printf( "%lf\n" , maxP * 100  );
    }
    return 0;
}