# C 程序：使用多维数组将两个矩阵相乘 > 原文： [https://www.programiz.com/c-programming/examples/matrix-multiplication](https://www.programiz.com/c-programming/examples/matrix-multiplication) #### 在此示例中，您将学习将两个矩阵相乘并使用用户定义的函数进行显示。 要理解此示例，您应该了解以下 [C 编程](/c-programming "C tutorial")主题： * [C 数组](/c-programming/c-arrays) * [C 多维数组](/c-programming/c-multi-dimensional-arrays) * * * 该程序要求用户输入两个矩阵的大小（行和列）。 为了将两个矩阵相乘，**第一个矩阵的列数应等于第二个矩阵的行数**。 下面的程序要求两个矩阵的行数和列数，直到满足上述条件。 然后，执行两个矩阵的相乘，结果显示在屏幕上。 为此，我们创建了三个函数： * `enterData()` - 从用户那里获取矩阵元素。 * `multiplyMatrices()` - 将两个矩阵相乘。 * `display()` - 显示相乘后的结果矩阵。 * * * ## 通过将矩阵传递给函数来相乘 ```c #include <stdio.h> void enterData(int first[][10], int second[][10], int r1, int c1, int r2, int c2); void multiplyMatrices(int first[][10], int second[][10], int multResult[][10], int r1, int c1, int r2, int c2); void display(int mult[][10], int r1, int c2); int main() { int first[10][10], second[10][10], mult[10][10], r1, c1, r2, c2; printf("Enter rows and column for the first matrix: "); scanf("%d %d", &r1, &c1); printf("Enter rows and column for the second matrix: "); scanf("%d %d", &r2, &c2); // Taking input until columns of the first matrix is equal to the rows of the second matrix while (c1 != r2) { printf("Error! Enter rows and columns again.\n"); printf("Enter rows and columns for the first matrix: "); scanf("%d%d", &r1, &c1); printf("Enter rows and columns for the second matrix: "); scanf("%d%d", &r2, &c2); } // Function to take matrices data enterData(first, second, r1, c1, r2, c2); // Function to multiply two matrices. multiplyMatrices(first, second, mult, r1, c1, r2, c2); // Function to display resultant matrix after multiplication. display(mult, r1, c2); return 0; } void enterData(int first[][10], int second[][10], int r1, int c1, int r2, int c2) { printf("\nEnter elements of matrix 1:\n"); for (int i = 0; i < r1; ++i) { for (int j = 0; j < c1; ++j) { printf("Enter a%d%d: ", i + 1, j + 1); scanf("%d", &first[i][j]); } } printf("\nEnter elements of matrix 2:\n"); for (int i = 0; i < r2; ++i) { for (int j = 0; j < c2; ++j) { printf("Enter b%d%d: ", i + 1, j + 1); scanf("%d", &second[i][j]); } } } void multiplyMatrices(int first[][10], int second[][10], int mult[][10], int r1, int c1, int r2, int c2) { // Initializing elements of matrix mult to 0. for (int i = 0; i < r1; ++i) { for (int j = 0; j < c2; ++j) { mult[i][j] = 0; } } // Multiplying first and second matrices and storing in mult. for (int i = 0; i < r1; ++i) { for (int j = 0; j < c2; ++j) { for (int k = 0; k < c1; ++k) { mult[i][j] += first[i][k] * second[k][j]; } } } } void display(int mult[][10], int r1, int c2) { printf("\nOutput Matrix:\n"); for (int i = 0; i < r1; ++i) { for (int j = 0; j < c2; ++j) { printf("%d ", mult[i][j]); if (j == c2 - 1) printf("\n"); } } } ``` **输出** ```c Enter rows and column for the first matrix: 2 3 Enter rows and column for the second matrix: 3 2 Enter elements of matrix 1: Enter a11: 3 Enter a12: -2 Enter a13: 5 Enter a21: 3 Enter a22: 0 Enter a23: 4 Enter elements of matrix 2: Enter b11: 2 Enter b12: 3 Enter b21: -9 Enter b22: 0 Enter b31: 0 Enter b32: 4 Output Matrix: 24 29 6 25 ```