原题http://acm.hdu.edu.cn/showproblem.php?pid=4920
Matrix multiplication
Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 131072/131072 K (Java/Others)
Total Submission(s): 848 Accepted Submission(s): 339
Problem Description Given two matrices A and B of size n×n, find the product of them.
bobo hates big integers. So you are only asked to find the result modulo 3.
Input The input consists of several tests. For each tests:
The first line contains n (1≤n≤800). Each of the following n lines contain n integers -- the description of the matrix A. The j-th integer in the i-th line equals A
ij. The next n lines describe the matrix B in similar format (0≤A
ij,B
ij≤10
9).
Output For each tests:
Print n lines. Each of them contain n integers -- the matrix A×B in similar format.
Sample Input
1
0
1
2
0 1
2 3
4 5
6 7
Sample Output
0
0 1
2 1
Author Xiaoxu Guo (ftiasch)
Source 2014 Multi-University Training Contest 5
Recommend We have carefully selected several similar problems for you: 4919 4918 4917 4916 4915
//开始的时候还以为这题要用到什么高深的算法。后来发现很多人过了，估计就是小技巧了
//首先。乘法的运算时间要比加法多。所以能避免乘法，尽量优化掉。
//经过这题，发现C++比G++跑的要更快，同样的代码差了差不多0.4秒。比赛的时候就是由于交了G++T了好多次
//最后，说一句，骚年，虽然暴力不是万能的。但是没有加上小技巧的暴力是万万不能的。
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