4fd800b3a8 2011-02-23        kinaba: struct ProductOfDigits
4fd800b3a8 2011-02-23        kinaba: {
4fd800b3a8 2011-02-23        kinaba: 	int smallestNumber( int N )
4fd800b3a8 2011-02-23        kinaba: 	{
4fd800b3a8 2011-02-23        kinaba: 		if( N < 10 )
4fd800b3a8 2011-02-23        kinaba: 			return 1;
4fd800b3a8 2011-02-23        kinaba: 		int ans = 0;
4fd800b3a8 2011-02-23        kinaba: 		for(int d=9; d>=2; --d)
4fd800b3a8 2011-02-23        kinaba: 			while( N%d == 0 )
4fd800b3a8 2011-02-23        kinaba: 				N/=d, ans++;
4fd800b3a8 2011-02-23        kinaba: 		return N==1 ? ans : -1;
4fd800b3a8 2011-02-23        kinaba: 	}
4fd800b3a8 2011-02-23        kinaba: };