void sum(juzhen a, juzhen b, juzhen &c)
{
 int s=0;
 for (int i = 1; i <= a.m1(); i++)//A矩陣的M
  for (int j = 1; j <= b.n1(); j++)//B矩陣的S
  {
   for (k0 = 1; k0 <= a.n1(); k0++)//a.n1也就是b.m1(a的n，b的n)【行向量*列向量】
   {
    s += a.read(i,k0)*b.read(k0,j);
   }
    c.write(i, j, s);
    s = 0;
  }
}

#include<iostream>
#include <string>
using namespace std;
 
class juzhen
{
private:
 int m,n;//長寬
 int num[10][10] = {0};
 string name;
 
public:
  void size(int a,int b)
  { m = a;
  n = b; }
  void set()
  {
   cout << "此矩陣規(guī)模：" << this->m <<"，"<< this->n << endl;//=====？
   for (int i = 1; i <= this->m; i++)
    for (int j = 1; j <= this->n; j++)
    {
     cin >> this->num[i][j];
    }
   cout << "輸入完成"<< endl;
  }
  void display()
  {
   for (int i = 1; i <= this->m; i++)//===i為行號（第幾行），j為列號
    for (int j = 1; j <= this->n; j++)
    {
     cout << this->num[i][j] << " ";
    if (j == this->n) cout << endl;//先輸出再換行
    }
  }
  int read(int a, int b) { return num[a][b]; }//調(diào)用此函數(shù)，得[m][n]元素的值
  void write(int a, int b,int count) {  num[a][b]=count; }//第三個參數(shù)的值，傳遞給[a][b]元素
  int m1() { return m; }//調(diào)用得到矩陣的m
  int n1() { return n; }//調(diào)用得到矩陣的n
};
 
int m0, n0, s0, k0;//矩陣規(guī)模（容易搞混的東西）
 
void sum(juzhen a, juzhen b, juzhen &c)//矩陣相乘公式所在。。。【要改實參值的要用&引用】
{
 for (int i = 1; i <= a.m1(); i++)//A矩陣的M
  for (int j = 1; j <= b.n1(); j++)//B矩陣的S
  {
 
   int s = 0;
   for (k0 = 1; k0 <= a.n1(); k0++)//a.n1也就是b.m1(a的n，b的n)【行向量*列向量】
   {
    s += a.read(i,k0)*b.read(k0,j);//因為用了C++，所以沒那么直觀，就是a[i][k]*b[k][j]，套個for循環(huán)求累加和（就是高中時向量的點乘）
   }
    c.write(i, j, s);
  }
}
int main()
{
 juzhen A,B,C;
 cout << "設定m,s,n。A的m*s,B的s*n(橫條數(shù)*縱條數(shù))"<<endl;
 cin >> m0>> s0>> n0;
 A.size(m0, s0);
 B.size(s0, n0);
 
 C.size(m0, n0);
 
 A.set();
 B.set();
 
 sum(A, B, C);//C=A*B
 cout << "結果C的m*n：" << endl;
 C.display();
 
 return 0;
}

void sum(juzhen a, juzhen b, juzhen &c) 
//矩陣相乘公式所在。。?！疽膶崊⒅档囊?amp;引用】