#100. 矩阵乘法

https://loj.ac/s/1451310

LibreOJ/100/100.cpp

@@ -0,0 +1,68 @@
+#include <cstring>
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 1005,
+          mod = 1e9 + 7;
+
+int n, m, p;
+
+class Matrix {
+  private:
+    int data[N][N];
+
+  public:
+    Matrix() {
+        memset(data, 0x00, sizeof(data));
+    }
+
+    int* operator[](int i) {
+        return data[i];
+    }
+
+    Matrix operator*(Matrix b) const {
+        Matrix c;
+
+        for (int i = 1; i <= n; i++) {
+            for (int j = 1; j <= p; j++) {
+                for (int k = 1; k <= m; k++) {
+                    c[i][j] = (c[i][j] + 1ll * data[i][k] * b[k][j] % mod) % mod;
+                }
+            }
+        }
+
+        return c;
+    }
+} a, b, c;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+
+    cin >> n >> m >> p;
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= m; j++) {
+            cin >> a[i][j];
+        }
+    }
+
+    for (int i = 1; i <= m; i++) {
+        for (int j = 1; j <= p; j++) {
+            cin >> b[i][j];
+        }
+    }
+
+    c = a * b;
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= p; j++) {
+            cout << (c[i][j] % mod + mod) % mod << ' ';
+        }
+        cout << endl;
+    }
+
+    return 0;
+}