HDU-4364 Matrix operation

简单矩阵...

代码如下：

#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

unsigned int temp[5][5] = {
    {0, 0, 0, 0, 0},
    {0, 2, 3, 1, 1},
    {0, 1, 2, 3, 1},
    {0, 1, 1, 2, 3},
    {0, 3, 1, 1, 2}
};

unsigned int fix(unsigned int x)
{
    if (x > 0xff) {
        x ^= 0x1b;
    }
    return x % (0xff+1);
}

unsigned int op(unsigned int b, unsigned int a)
{
    if (b == 1) {
        return fix(a);    
    }
    else if (b == 2) {
        return fix(a << 1);    
    }
    else {
        return fix( fix(a << 1) ^ a );
    }
}

struct Matrix
{
    unsigned int a[5][5];
    Matrix unit ()
    {
        Matrix ret;
        for (unsigned int i = 1; i <= 4; ++i) {
            ret.a[i][i] = 1;    
        }
        return ret;
    }
    void zero(){
        memset(a, 0, sizeof(a)); 
    }
    Matrix operator * (Matrix temp) const
    {
        Matrix ret; 
        ret.zero();
        for ( int i = 1; i <= 4; ++i) {
            for ( int j = 1; j <= 4; ++j) {
                for ( int k = 1; k <= 4; ++k) {
                    ret.a[i][j] ^= op(a[i][k], temp.a[k][j]);
                    fix(ret.a[i][j]);
                }
            }
        }
        return ret;
    }
    void read()
    {
        for ( int i = 1; i <= 4; ++i) {
            for ( int j = 1; j <= 4; ++j) {
                scanf("%X", &a[i][j]);
            }
        }
    }
    void copy(unsigned int temp[][5])
    {
        for ( int i = 1; i <= 4; ++i) {
            for ( int j = 1; j <= 4; ++j) {
                a[i][j] = temp[i][j];
            }
        }
    }
    void print()
    {
        for (int i = 1; i <= 4; ++i) {
            for (int j = 1; j <= 4; ++j) {
                printf(j==1 ? "%02X" : " %02X", a[i][j]);
            }
            puts("");
        }
    }
}M, S, ret;

int main()
{
    unsigned int T;
    scanf("%u", &T);
    while (T--) {
        M.read();
        S.copy(temp);
        ret = S * M;
        ret.print();
        if (T > 0) {
            puts("");
        }
    }
    return 0;
}