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

#define SIZE 1024

void matmul(float** A, float** B, float** C, int n) {
    int i, j, k;
    for (i = 0; i < n; ++i) {
        for (j = 0; j < n; ++j) {
            C[i][j] = 0;
            for (k = 0; k < n; ++k) {
                C[i][j] += A[i][k] * B[k][j];
            }
        }
    }
}

int main() {
    float** A = (float**)malloc(SIZE * sizeof(float*));
    float** B = (float**)malloc(SIZE * sizeof(float*));
    float** C = (float**)malloc(SIZE * sizeof(float*));
    int i, j;
    for (i = 0; i < SIZE; ++i) {
        A[i] = (float*)malloc(SIZE * sizeof(float));
        B[i] = (float*)malloc(SIZE * sizeof(float));
        C[i] = (float*)malloc(SIZE * sizeof(float));
    }

    srand(time(0));
    for (i = 0; i < SIZE; ++i) {
        for (j = 0; j < SIZE; ++j) {
            A[i][j] = rand() % 100; 
            B[i][j] = rand() % 100; 
        }
    }
    clock_t start = clock();
    matmul(A, B, C, SIZE);
    clock_t end = clock();
    double time = (double)(end - start) / CLOCKS_PER_SEC;
    printf("%f\n", time);

    for (i = 0; i < SIZE; ++i) {
        free(A[i]);
        free(B[i]);
        free(C[i]);
    }
    free(A);
    free(B);
    free(C);
    return 0;
}