用c语言利用稀疏矩阵三元组存储实现矩阵的相加算法和转置算法

矩阵相加算法：

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

typedef struct {
    int row;
    int col;
    int val;
} Triple;

void matrix_add(Triple a[], int a_len, Triple b[], int b_len, Triple c[], int *c_len) {
    if (a_len == 0 && b_len == 0) {
        *c_len = 0;
        return;
    }
    if (a_len == 0) {
        *c_len = b_len;
        for (int i = 0; i < b_len; i++) {
            c[i] = b[i];
        }
        return;
    }
    if (b_len == 0) {
        *c_len = a_len;
        for (int i = 0; i < a_len; i++) {
            c[i] = a[i];
        }
        return;
    }
    if (a[0].row > b[0].row || (a[0].row == b[0].row && a[0].col > b[0].col)) {
        matrix_add(b, b_len, a, a_len, c, c_len);
        return;
    }
    int i = 0, j = 0, k = 0;
    while (i < a_len && j < b_len) {
        if (a[i].row < b[j].row || (a[i].row == b[j].row && a[i].col < b[j].col)) {
            c[k++] = a[i++];
        } else if (a[i].row > b[j].row || (a[i].row == b[j].row && a[i].col > b[j].col)) {
            c[k++] = b[j++];
        } else {
            int val = a[i].val + b[j].val;
            if (val != 0) {
                c[k].row = a[i].row;
                c[k].col = a[i].col;
                c[k].val = val;
                k++;
            }
            i++;
            j++;
        }
    }
    while (i < a_len) {
        c[k++] = a[i++];
    }
    while (j < b_len) {
        c[k++] = b[j++];
    }
    *c_len = k;
}

int main() {
    Triple a[3] = {{0, 0, 1}, {1, 1, 2}, {2, 2, 3}};
    int a_len = 3;
    Triple b[3] = {{0, 0, 1}, {1, 1, 2}, {2, 2, 3}};
    int b_len = 3;
    Triple c[6];
    int c_len;
    matrix_add(a, a_len, b, b_len, c, &c_len);
    for (int i = 0; i < c_len; i++) {
        printf("(%d, %d, %d)\n", c[i].row, c[i].col, c[i].val);
    }
    return 0;
}

矩阵转置算法：

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

typedef struct {
    int row;
    int col;
    int val;
} Triple;

void matrix_transpose(Triple a[], int a_len, Triple b[], int *b_len, int m, int n) {
    if (a_len == 0) {
        *b_len = 0;
        return;
    }
    int num[m], cpot[m];
    for (int i = 0; i < m; i++) {
        num[i] = 0;
    }
    for (int i = 0; i < a_len; i++) {
        num[a[i].col]++;
    }
    cpot[0] = 0;
    for (int i = 1; i < m; i++) {
        cpot[i] = cpot[i - 1] + num[i - 1];
    }
    for (int i = 0; i < a_len; i++) {
        int j = cpot[a[i].col]++;
        b[j].row = a[i].col;
        b[j].col = a[i].row;
        b[j].val = a[i].val;
    }
    *b_len = a_len;
}

int main() {
    Triple a[3] = {{0, 0, 1}, {1, 1, 2}, {2, 2, 3}};
    int a_len = 3;
    Triple b[3];
    int b_len;
    matrix_transpose(a, a_len, b, &b_len, 3, 3);
    for (int i = 0; i < b_len; i++) {
        printf("(%d, %d, %d)\n", b[i].row, b[i].col, b[i].val);
    }
    return 0;
}