（数据结构）部分稀疏矩阵的操作

Posted 2020-08-14

//顺序
typedef struct {
    int row,
    col; //非零元素的行号、列号
    ElemType val; //元素值
}
Triple;
typedef struct {
    int m,
    n,
    t; //矩阵的行、列数及非零元素个数
    Triple sm[MaxTerms + 1]; //三元组线性表，从sm[1]开始                             
}
SMatrix;

void InitMatrix(SMatrix & M) {
    M.m = 0;
    M.n = 0;
    M.t = 0;
}
void InputMatrix(SMatrix & M, int m, int n) { //以行序为主序次序每行输入一个三元组，最后以 “0 0 0” 结束
    int row,
    col,
    val,
    k = 0;
    cin >> row >> col >> val;
    while (row != 0) {
        k++;
        M.sm[k].row = row;
        M.sm[k].col = col;
        M.sm[k].val = val;
        cin >> row >> col >> val;
    }
    M.m = m;
    M.n = n;
    M.t = k;
}

//链式
typedef struct Node {
    int row,
    col; //非零元素的行号、列号
    ElemType val; //元素值
    struct Node * next;
}
TripleNode;

typedef struct {
    int m,
    n,
    t; //矩阵的行、列数及非零元素个数
    TripleNode * vector[MaxRows + 1]; //从vector[1]开始                          
}
LMatrix;

void InitMatrix(LMatrix & M) {
    M.m = 0;
    M.n = 0;
    M.t = 0;
    for (int i = 1; i <= MaxRows; i++) M.vector[i] = NULL;
}
void InputMatrix(LMatrix & M, int m, int n) { //以行序为主序次序每行输入一个三元组，最后以 “0 0 0” 结束
    TripleNode * p,
    *q;
    int row,
    col,
    val,
    k = 0;
    cin >> row >> col >> val;
    while (row != 0) {
        k++;
        p = new TripleNode;
        p - >row = row;
        p - >col = col;
        p - >val = val;
        p - >next = NULL;
        //插在单链表末尾
        q = M.vector[row];
        if (q == NULL) M.vector[row] = p;
        else {
            while (q - >next != NULL) q = q - >next;
            q - >next = p;
        }
        cin >> row >> col >> val;
    }
    M.m = m;
    M.n = n;
    M.t = k;
}

/*--------------------*/

SMatrix Transpose(SMatrix M) //转置
{
    int k = 1;
    SMatrix S;
    InitMatrix(S);
    S.m = M.n;
    S.n = M.m;
    S.t = M.t;
    if (S.t == 0) return S;
    for (int col = 1; col <= M.n; col++) for (int i = 1; i <= M.t; i++) if (M.sm[i].col == col) {
        S.sm[k].row = M.sm[i].col;
        S.sm[k].col = M.sm[i].row;
        S.sm[k].val = M.sm[i].val;
        k++;
    }
    return S;
}
LMatrix Add(LMatrix M1, LMatrix M2) {
    int k = 0; //统计非零元个数
    Triple * p1,
    *p2,
    *p,
    *newptr;
    LMatrix M;
    InitMatrix(M);
    M.m = M1.m;
    M.n = M1.n;
    if ((M1.t == 0) && (M2.t == 0)) return M;
    for (int i = 1; i <= M1.m; i++) {
        p1 = M1.vector[i];
        p2 = M2.vector[i];
        p = NULL;
        while ((p1 != NULL) && (p2 != NULL)) {
            if (p1 - >col < p2 - >col) {
                newptr = new TripleNode; * newptr = *p1;
                p1 = p1 - >next;
            } else if (p1 - >col > p2 - >col) {
                newptr = new TripleNode; * newptr = *p2;
                p2 = p2 - >next;
            } else {
                if (p1 - >val + p2 - >val == 0) {
                    p1 = p1 - >next;
                    p2 = p2 - >next;
                    continue;
                } else {
                    newptr = new TripleNode; * newptr = *p1;
                    newptr - >val += p2 - >val;
                    p1 = p1 - >next;
                    p2 = p2 - >next;
                }
            }
            //以下插入newptr到第i行链尾，并后移p指针
            newptr - >next = NULL;
            if (p == NULL) M.vector[i] = newptr;
            else p - >next = newptr;
            p = newptr;
            k++;
        } //while
        while (p1 != NULL) {
            newptr = new TripleNode; * newptr = *p1;
            newptr - >next = NULL;
            if (p == NULL) M.vector[i] = newptr;
            else p - >next = newptr;
            p = newptr;
            p1 = p1 - >next;
            k++;
        } //while
        while (p2 != NULL) {
            newptr = new TripleNode; * newptr = *p2;
            newptr - >next = NULL;
            if (p == NULL) M.vector[i] = newptr;
            else p - >next = newptr;
            p = newptr;
            p2 = p2 - >next;
            k++;
        } //while
    } //for
    M.t = k;
    return M;
}