1483 稀疏矩阵的压缩存储与相乘

 1 //稀疏矩阵乘法 行逻辑链接的三元组顺序表
 2 // 3 4
 3 // 6
 4 // 1 1 3
 5 // 1 2 2
 6 // 1 3 3
 7 // 1 4 5
 8 // 2 2 -1
 9 // 3 1 2
10 // 4 2
11 // 5
12 // 1 2 2
13 // 2 1 1
14 // 3 1 -2
15 // 3 2 4
16 // 4 1 2
17 #include <iostream>
18 #include <cstring>
19 #define  MAX_SIZE 2500+1
20 #define  MAX_RC   2500+1
21 using namespace std;
22 typedef int elemType;
23 typedef struct {
24     int i,j;
25     elemType e;
26 }Triple;
27 typedef struct{
28     Triple data[MAX_SIZE];
29     int    rowPos[MAX_RC];//各行第一个元素的秩表
30     int    mu,nu,tu;
31 }TripleSpareMatrix;
32 void creatTripleSpareMatrix(TripleSpareMatrix &tSM)
33 {
34     scanf("%d%d%d",&tSM.mu,&tSM.nu,&tSM.tu);
35     int rowNum[tSM.mu+1];
36     for (int i = 0; i < tSM.mu+1; ++i) rowNum[i]=0;//行元素数目累加器初始化
37     for(int k=1;k<=tSM.tu;k++)
38     {
39         scanf("%d%d%d",&tSM.data[k].i,&tSM.data[k].j,&tSM.data[k].e);
40         rowNum[tSM.data[k].i]++;
41     }
42     tSM.rowPos[1]=1;
43     for (int p = 2; p <=tSM.mu+1; ++p)//对不存在的第[tSm.mu+1]行统一处理
44         tSM.rowPos[p]=tSM.rowPos[p-1]+rowNum[p-1];
45 }
46 void multMatrix(TripleSpareMatrix tSM1,TripleSpareMatrix tSM2,TripleSpareMatrix &tSM3)
47 {
48     tSM3.mu=tSM1.mu; tSM3.nu=tSM2.nu; tSM3.tu=0;//tSM3初始化
49     for (int row = 1; row <= tSM1.mu; ++row)//遍历tSM3（同tSM1）的每一行
50     {
51         int colNum[tSM2.nu+1];
52         for (int i = 0; i < tSM2.nu+1; ++i) colNum[i]=0;//当前行个元素累加器初始化
53         tSM3.rowPos[row]=tSM3.tu+1;//
54         for (int p = tSM1.rowPos[row]; p <tSM1.rowPos[row+1]; ++p)//遍历当前的row行的每一个非零元
55             for (int q=tSM2.rowPos[tSM1.data[p].j]; q<tSM2.rowPos[tSM1.data[p].j+1]; ++q)//遍历与tSM1当前行的对应tSM2行（tSM1.data[p].j==tSM2.data[q].i）
56                 colNum[tSM2.data[q].j]+=tSM1.data[p].e*tSM2.data[q].e;//累加
57         for (int col = 1; col <= tSM2.nu; ++col)//压缩存储非零元
58             if(colNum[col])
59             {
60                 tSM3.tu++;
61                 tSM3.data[tSM3.tu].i=row; tSM3.data[tSM3.tu].j=col; tSM3.data[tSM3.tu].e=colNum[col];
62             }
63     }
64 }
65 void printMatrix(TripleSpareMatrix tSM)
66 {
67     for (int i = 1; i <=tSM.tu; ++i)
68         printf("%d %d %d\n",tSM.data[i].i,tSM.data[i].j,tSM.data[i].e );
69 }
70 int main(int argc, char const *argv[])
71 {
72     #ifndef _OJ_  //ONLINE_JUDGE
73     freopen("input.txt", "r", stdin);
74     #endif
75     TripleSpareMatrix tSM1,tSM2,tSM3;
76     creatTripleSpareMatrix(tSM1);
77     creatTripleSpareMatrix(tSM2);
78     multMatrix(tSM1,tSM2,tSM3);
79     printMatrix(tSM3);
80     return 0;
81 }