[编译原理代码][NFA转DFA并最小化DFA并使用DFA进行词法分析]

#include <iostream>
#include <vector>
#include <cstring>
#include "stack"
#include "algorithm"
using namespace std;
int NFAStatusNum,AlphabetNum,StatusEdgeNum,AcceptStatusNum;
char alphabet[1000];
int accept[1000];
int StartStatus;
int isDFAok=1;
int isDFA[1000][1000];
/*
 *   NFA状态图的邻接表
 */

vector<vector<int>> Dstates;
int Dstatesvisit[1000];
int Dtran[1000][1000];
vector<int> Dtranstart;
vector<int> Dtranend;
int isDtranstart[1000];
int isDtranend[1000];
class Edge{
public:
    int to,w,next;
} ;
Edge edge[10000];
int edgetot=0;
int Graph[1000];
void link(int u,int v,int w){
    edge[++edgetot].to=v;edge[edgetot].w=w;edge[edgetot].next=Graph[u];Graph[u]=edgetot;
}

void input(){
    int u,v,w;
    memset(Dtran,-1,sizeof(Dtran));
    scanf("%d %d %d %d
",&NFAStatusNum,&AlphabetNum,&StatusEdgeNum,&AcceptStatusNum);
    for(int i=1;i<=AlphabetNum;i++){    //读入字母表
        scanf("%c",&alphabet[i]);
    }
    for(int i=1;i<=AcceptStatusNum;i++){
        scanf("%d",&accept[i]);
    }
    //开始状态序号
    scanf("%d",&StartStatus);
    for(int i=0;i<StatusEdgeNum;i++){
        scanf("%d%d%d
",&u,&v,&w);
        link(u,v,w);

        if(isDFA[u][v]==0){
            isDFA[u][v]=1;
        }
        else{
            isDFAok=0;
        }
        if(w==0){
            isDFAok=0;
        }
    }
    //读入测试字符串

}
void e_clouser(vector<int> &T,vector<int> &ans){
    int visit[1000];
    memset(visit,0,sizeof(visit));
    stack<int> Stack;
    //T all push in Stack and copy to ans
    for (int i=0;i < T.size();++i){
        Stack.push(T[i]);
        ans.push_back(T[i]);
        visit[T[i]]=1;
    }
    while(Stack.empty()!=1){
        int t = Stack.top(); Stack.pop();
        for(int p=Graph[t];p!=0;p=edge[p].next){
            if(edge[p].w==0){
                if(visit[edge[p].to]==0){
                    visit[edge[p].to]=1;
                    Stack.push(edge[p].to);
                    ans.push_back(edge[p].to);
                }
            }
        }
    }
    sort(ans.begin(),ans.end());
}

void move(vector<int> &T,int a,vector<int> &ans){
    int visit[1000];
    memset(visit,0,sizeof(visit));
    for(int i=0;i<T.size();i++) {
        int t=T[i];
        for (int p = Graph[t]; p != 0; p = edge[p].next) {
            if (edge[p].w == a) {
                if (visit[edge[p].to] == 0) {
                    visit[edge[p].to] = 1;
                    ans.push_back(edge[p].to);
                }
            }
        }
    }
}
bool notin(vector<int> &a,int &U){
    for(int i=0;i<Dstates.size();i++){
        int ok=1;
        if(Dstates[i].size()==a.size()){
            for(int j=0;j<a.size();j++){
                if(Dstates[i][j]!=a[j]){
                    ok=0;
                    break;
                }
            }
            if(ok==1) {
                U=i;
                return false;
            }
        }
    }
    U=Dstates.size();
    return true;
}
void nfatodfa(){
        vector<int> s,t;
        s.push_back(StartStatus);
        e_clouser(s,t);
        Dstates.push_back(t);
        stack<int> Stack;
        Stack.push(Dstates.size()-1);
        while(Stack.empty()!=1){
            int T=Stack.top();Stack.pop();int U;
            for(int i=1;i<=AlphabetNum;i++){
                vector<int> ans,ans2;
                move(Dstates[T],i,ans2);
                e_clouser(ans2,ans);
                if(notin(ans,U)){
                    Dstates.push_back(ans);
                    Stack.push(Dstates.size()-1);
                }
                Dtran[T][i]=U;
            }
        }
}
void getDtranStartEnd(){
    for(int i=0;i<Dstates.size();i++){
        int ok=1;
        for(int j=0;j<Dstates[i].size();j++){
            if(Dstates[i][j]==StartStatus){
                Dtranstart.push_back(i);
                isDtranstart[i]=1;
            }
            if(ok){
                for(int k=1;k<=AcceptStatusNum;k++){
                    if(Dstates[i][j]==accept[k]){
                        ok=0;
                        Dtranend.push_back(i);
                        isDtranend[i]=1;
                    }
                }
            }
        }
    }
}
vector<vector<int>> newDstates;
int newDstatesvisit[1000];
int newDtran[1000][1000];
int set[1000];
vector<int> newDtranstart;
vector<int> newDtranend;
int isnewDtranstart[1000];
int isnewDtranend[1000];
void simple(){
    int visit[1000];
    memset(visit,0,sizeof(visit));
    vector<int> a,b;
    //接受结点加入a
    for(int i=0;i<Dtranend.size();i++){
        a.push_back(Dtranend[i]);
        visit[Dtranend[i]]=1;
        set[Dtranend[i]]=0;
    }
    //剩余结点加入b
    for(int i=0;i<Dstates.size();i++){
        if(visit[i]==0){
            b.push_back(i);
            set[i]=1;
        }
    }
    newDstates.push_back(a);
    newDstates.push_back(b);
    while(1){
        int ok=0;
        for(int i=0;i<newDstates.size();i++){
            for (int k = 1; k <= AlphabetNum; k++) {
                    for(int j=1;j<newDstates[i].size();j++) {
                        int pp= Dtran[newDstates[i][0]][k];
                        int u = newDstates[i][j], v = Dtran[u][k];
                        if (set[v] != set[pp] ) {
                            //将u剥离
                            newDstates[i].erase(newDstates[i].begin() + j);
                            vector<int> temp;
                            temp.push_back(u);
                            set[u] = newDstates.size();
                            newDstates.push_back(temp);
                            ok = 1;
                            break;
                        }
                        if (ok == 1) break;
                    }
                if(ok==1) break;
            }
            if(ok==1) break;
        }
        if(ok==0) break;
    }
    //isnewDtranstart,isnewDtranend,newDtran
    for(int i=0;i<Dstates.size();i++) {
        for (int j = 1; j <= AlphabetNum; j++) {
            newDtran[set[i]][j]=set[Dtran[i][j]];
        }
        if(isDtranend[i]==1)
            isnewDtranend[set[i]]=1;
        if(isDtranstart[i]==1)
            isnewDtranstart[set[i]]=1;
    }
    //isnewDtranstart,isnewDtranend

}

bool dfa(char *S){
    int index=0;
    int status=0;
    for(int i=0;i<newDstates.size();i++){
        if(isnewDtranstart[i]==1){
            status=i;
        }
    }
    for(int i=0;i<strlen(S);i++) {
            //这里我偷懒了,懒得弄个map存映射,直接对这个例子进行操作,就是 S[i]-'a'+1;
        int p=S[i]-'a'+1;
        status=newDtran[status][p];
    }
    if(isnewDtranend[status]==1) return true;
    else return false;
}

int main() {
    freopen("E:\NFATODFA\a.in","r",stdin);
    input();
    if(isDFAok==0){
        printf("This is NFA
");
        nfatodfa();
    }
    else{

        printf("This is DNA
");
    }
    //打印DFA
    printf("
Print DFA's Dtran:
");
    printf("        DFAstatu  a     b");
    getDtranStartEnd();
    for(int i=0;i<Dstates.size();i++){
        printf("
");
        if(isDtranstart[i]==1)
            printf("start   ");
        else if(isDtranend[i]==1)
            printf("end     ");
        else printf("        ");
        printf("%5c ",i+'A');
        for(int j=1;j<=AlphabetNum;j++)
            printf("%5c ",Dtran[i][j]+'A');
    }
    printf("
Print simple DFA's Dtran:
");
    simple();
    printf("        DFAstatu  a     b");
    for(int i=0;i<newDstates.size();i++){
        printf("
");
        if(isnewDtranstart[i]==1)
            printf("start   ");
        else if(isnewDtranend[i]==1)
            printf("end     ");
        else printf("        ");
        printf("%5c ",i+'A');
        for(int j=1;j<=AlphabetNum;j++)
            printf("%5c ",newDtran[i][j]+'A');
    }
    printf("
");
    char S[1000];
    while(scanf("%s
",S)!=EOF){
        if(dfa(S)){
            printf("%s belongs to the DFA
",S);
        }
        else
            printf("%s don't belong to the DFA
",S);
    }
    return 0;
}