根据Strassen矩阵乘法的分治思想，用C++实现两个矩阵的乘法，要求如下： 1） 输入矩阵维数m和n； 2） 自动生成两个矩阵的元素（为正整数），输出保存到文件matriaA.txt和matriaB.txt。

3）从文件matriaA.txt和matriaB.txt中读入两个矩阵； 4）计算两个矩阵的乘积，并输出结果保存到文件matriaC.txt。

以下是代码实现：

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

void generate_matrix(int m, int n, char* filename) {
    FILE* fp = fopen(filename, "w");
    srand(time(NULL)); //设置随机种子
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < n; j++) {
            int num = rand() % 10 + 1; //生成1~10的随机数
            fprintf(fp, "%d ", num);
        }
        fprintf(fp, "\n");
    }
    fclose(fp);
}

void read_matrix(int m, int n, char* filename, int matrix[m][n]) {
    FILE* fp = fopen(filename, "r");
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < n; j++) {
            fscanf(fp, "%d", &matrix[i][j]);
        }
    }
    fclose(fp);
}

void write_matrix(int m, int n, char* filename, int matrix[m][n]) {
    FILE* fp = fopen(filename, "w");
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < n; j++) {
            fprintf(fp, "%d ", matrix[i][j]);
        }
        fprintf(fp, "\n");
    }
    fclose(fp);
}

void strassen(int m, int n, int A[m][n], int B[m][n], int C[m][n]) {
    if (m == 1 && n == 1) {
        C[0][0] = A[0][0] * B[0][0];
        return;
    }
    int p = m / 2, q = n / 2;
    int A11[p][q], A12[p][q], A21[p][q], A22[p][q];
    int B11[p][q], B12[p][q], B21[p][q], B22[p][q];
    int C11[p][q], C12[p][q], C21[p][q], C22[p][q];
    int P1[p][q], P2[p][q], P3[p][q], P4[p][q], P5[p][q], P6[p][q], P7[p][q];
    //将矩阵A和B分成四个子矩阵
    for (int i = 0; i < p; i++) {
        for (int j = 0; j < q; j++) {
            A11[i][j] = A[i][j];
            A12[i][j] = A[i][j + q];
            A21[i][j] = A[i + p][j];
            A22[i][j] = A[i + p][j + q];

            B11[i][j] = B[i][j];
            B12[i][j] = B[i][j + q];
            B21[i][j] = B[i + p][j];
            B22[i][j] = B[i + p][j + q];
        }
    }
    //计算七个矩阵乘积
    strassen(p, q, A11, B11, P1);
    strassen(p, q, A12, B21, P2);
    strassen(p, q, A11, B12, P3);
    strassen(p, q, A12, B22, P4);
    strassen(p, q, A21, B11, P5);
    strassen(p, q, A22, B21, P6);
    strassen(p, q, A21, B12, P7);
    //计算C11~C22
    for (int i = 0; i < p; i++) {
        for (int j = 0; j < q; j++) {
            C11[i][j] = P1[i][j] + P2[i][j];
            C12[i][j] = P3[i][j] + P4[i][j];
            C21[i][j] = P5[i][j] + P6[i][j];
            C22[i][j] = P7[i][j] - P2[i][j] + P4[i][j] + P6[i][j];
        }
    }
    //将C11~C22合并成C
    for (int i = 0; i < p; i++) {
        for (int j = 0; j < q; j++) {
            C[i][j] = C11[i][j];
            C[i][j + q] = C12[i][j];
            C[i + p][j] = C21[i][j];
            C[i + p][j + q] = C22[i][j];
        }
    }
}

int main() {
    int m, n;
    printf("Please input the dimension of matrix (m,n): ");
    scanf("%d,%d", &m, &n);
    int A[m][n], B[m][n], C[m][n];
    generate_matrix(m, n, "matriaA.txt");
    generate_matrix(m, n, "matriaB.txt");
    read_matrix(m, n, "matriaA.txt", A);
    read_matrix(m, n, "matriaB.txt", B);
    strassen(m, n, A, B, C);
    write_matrix(m, n, "matriaC.txt", C);
    printf("The result has been saved to file matriaC.txt.\n");
    return 0;
}

注意事项：

- 代码中使用了递归函数，递归深度可能很大，如果数据规模很大，应该使用非递归的实现方式；
- 代码中使用了动态数组，如果使用静态数组，需要在函数参数中将数组大小明确指定；
- 代码中使用了文件读写操作，需要确认文件是否存在以及文件读写操作是否成功。