#include <iostream.h>
#include <iomanip.h>

int a[3][4]={{ 5, 7, 8, 2},
{-2, 4, 1, 1},
{ 1, 2, 3, 4}};

int b[4][5]={{4,-2, 3, 3, 9},
{4, 3, 8,-1, 2},
{2, 3, 5, 2, 7},
{1, 0, 6, 3, 4}};

int c[3][5];

bool MultiMatrix(int a[3][4], int arow, int acol,
int b[4][5], int brow, int bcol,
int c[3][5], int crow, int ccol); //函数声明

void main()
{
if(MultiMatrix(a,3,4, b,4,5, c,3,5)){
cout <<"illegal matrix multiply.\n";
return;
}

for(int i=0; i<3; i++){ //输出矩阵乘法的结果
for(int j=0; j<5; j++)
cout <<setw(5) <<c[i][j];
cout <<endl;
}
}

bool MultiMatrix(int a[3][4], int arow, int acol,
int b[4][5], int brow, int bcol,
int c[3][5], int crow, int ccol)
{
if(!((acol==brow)&&(crow==arow)&&(ccol==bcol))) //正确性检查
return 1;

for(int i=0; i<crow; i++) //行
for(int j=0; j<ccol; j++){ //列
c[i][j]=0; //此句可以省略，因为c是全局数组
for(int n=0; n<acol; n++) //求一个元素
c[i][j]+= a[i][n] * b[n][j];
}

return 0;
}