C++实现离散数学的关系类，支持传递闭包运算

  1 #include <vector>
  2 #include <cassert>
  3 #include <iostream>
  4 using namespace std;
  5 class Graph{
  6 private:
  7     int n;
  8     int** graph;
  9 public:
 10     Graph(int n){
 11         this->n = n;
 12         graph = new int*[n];
 13         for(int i=0;i<n;i++)
 14             graph[i] = new int[n];
 15         for(int i=0;i<n;i++)
 16             for(int j=0;j<n;j++)
 17                 graph[i][j] = 0;
 18     }
 19     void addEdge(int a,int b){
 20         assert(a>0&&a<=n);
 21         assert(b>0&&b<=n);
 22         if(connected(a-1,b-1))
 23             return;
 24         graph[a-1][b-1] = 1;
 25     }
 26     void removeEdge(int a,int b){
 27         assert(a>0&&a<=n);
 28         assert(b>0&&b<=n);
 29         if(!connected(a,b))
 30             return;
 31         graph[a-1][b-1] = 0;
 32     }
 33     bool connected(int a,int b){
 34         return graph[a][b]==1;
 35     }
 36     void plus(int a1,int b1,int a2,int b2){
 37         if(graph[a1][b1]==0)
 38             graph[a1][b1]+=graph[a2][b2];
 39         else
 40             return;
 41     }
 42     void display(){
 43         cout<<"Matrix Form:"<<endl;
 44         for(int i=0;i<n;i++){
 45             for(int j = 0;j<n;j++)
 46                 cout<<graph[i][j]<<" ";
 47             cout<<endl;
 48         }
 49         cout<<"Front: ";
 50         for(int i=0;i<n;i++)
 51             for(int j=0;j<n;j++){
 52                 if(graph[i][j])
 53                     cout<<"<"<<i+1<<","<<j+1<<">  ";
 54         }
 55         cout<<endl;
 56     }
 57 };
 58 
 59 class RelationShip{
 60 private:
 61     bool print;
 62     int num_points;
 63     Graph graph;
 64 public:
 65     RelationShip(int num):graph(num){
 66         print = true;
 67         this->num_points = num;
 68     }
 69 
 70     void add_RS(int a,int b){
 71         graph.addEdge(a,b);
 72     }
 73 
 74     void remove_RS(int a,int b){
 75         graph.removeEdge(a,b);
 76     }
 77 
 78     void transfer(){ //将矩阵作传递化闭包运算
 79         for(int i = 0;i<num_points;i++){
 80             for(int j = 0;j<num_points;j++){
 81                 if(graph.connected(j,i)){
 82                     for(int k = 0;k<num_points;k++)
 83                         graph.plus(j,k,i,k);
 84                 }
 85             }
 86         }
 87         print = true;
 88     }
 89 
 90     void show(){
 91         graph.display();
 92     }
 93 };
 94 
 95 int main(){
 96     cout<<"请输入你希望的元素个数:"<<endl;
 97     int n;
 98     while(cin>>n){
 99         RelationShip op = RelationShip(n);
100         int num;
101         cout<<"你想联系起多少对关系呢？"<<endl;
102         cin>>num;
103         while(num--){
104             cout<<"请输入[1,"<<n<<"]之间的任意一对序偶"<<endl;
105             int a,b;
106             cin>>a>>b;
107             op.add_RS(a,b);
108         }
109         cout<<"你想进行传递闭包运算吗？(yes or no)"<<endl;
110         string s;
111         cin>>s;
112         if(s=="yes")
113             op.transfer();
114         op.show();
115     }
116 }