编译原理上机作业4——LR(0)分析的DFA生成

input文件

=*iXSLRX->SS->L=RS->RL->*RL->iR->L#

code

#include <iostream>#include <cstdio>#include <cstdlib>#include <cstring>#include <queue>#define INIT_LIST -1#define HAVE_LIST 1using namespace std;typedef struct grammer{char content[24];// init value: "\0"int s_pos;// init value: 3int s_len;// init value: -1}grammer;typedef struct item{int id;grammer gram[200];// init value: see grammerint next[200];//init value: all -1int num;}item;/*  global variable */item my_item[200];item stand;//queue<item> process;item process[1000];char terSymbol[200];char nterSymbol[200];char Symbol[400];int vtnum, vnnum, vnum, id = 0;int front = 0, rear = 0;/* functions */void closure( item & temp );int is_nterminal( char ch );int local( char x );bool do_not_have( int x, item temp );bool same( item a, item b[] /* b is my_item*/ );void init( item temp[], int num );void input();void add_to_item( int yuan, int sym, item temp );void add( int i, int j, item temp[], item current );bool end( item temp );int local( char x );int is_nterminal( char ch );void print_item( );void next( item & temp );bool can_closure( item temp );bool cmp( item a, item b );int main(){freopen( "input.txt", "r", stdin );init( my_item, 200 );input();item ini;ini.id = 1;ini.num = 1;strcpy( ini.gram[0].content, my_item[0].gram[0].content );ini.gram[0].s_len = strlen( ini.gram[0].content);ini.gram[0].s_pos = 3;closure( ini );next( ini );id = 1;my_item[id] = ini;//add_to_item( my_item[id] );//process.push( ini );process[rear++] = ini;//don't forget :)my_item[0].id = 1;//while(!process.empty())while( front < rear ) { /* the C++ STL pop() functions doesn't return a value you need to use front() to r eturn a value and use pop() to pop the top of the queue make them happy :) */    //item current = process.front();    //process.pop();item current = process[front++];item temp[vnum];init( temp, vnum );for( int i = 0; i < vnum; i++ ){if( current.next[i] == HAVE_LIST ){for( int j = 0; j < current.num; j++ )add( i, j, temp, current );closure( temp[i] );next( temp[i] );if( same( temp[i], my_item ) ){my_item[id].next[i] = id;}else{add_to_item( current.id, i, temp[i]/*add to my_item[id]*/ );if( !end( temp[i] ) )//process.push( temp[i] );//process[rear++] = temp[i];process[rear++] = my_item[id-1];}}}}print_item();}void next( item & temp ){for( int i = 0; i < temp.num; i++ ){if( temp.gram[i].s_pos < temp.gram[i].s_len )temp.next[local(temp.gram[i].content[temp.gram[i].s_pos])] = HAVE_LIST;}}void print_item( ){for( int i = 0; i < id; i++ ){cout << my_item[i].id << endl;for( int j = 0; j < my_item[i].num; j++ ){cout << my_item[i].gram[j].content << "  ";}cout << endl;cout << "from:";for( int t = 0; t < vnum; t++ )cout << Symbol[t] << " ";cout << "    " << endl; for( int t = 0; t < vnum; t++ )cout << my_item[i].next[t] << " ";cout << endl;cout << endl;}}bool end( item temp ){for( int i = 0; i < temp.num; i++ ){if( temp.gram[i].s_pos < temp.gram[i].s_len )return false; }return true;}void add_to_item( int yuan, int sym, item temp ){/*  add temp to my_item set */int last = id++;my_item[last] = temp;my_item[last].id = id;/*  last my_item's point to the new my_item */my_item[yuan].next[sym] = id;}bool cmp( item a, item b ){int flag = 0;for( int i = 0; i < a.num; i++ ){flag = 0;for( int j = 0; j < b.num; j++ ){if( !strcmp(a.gram[i].content, b.gram[j].content) ){flag = 1;break;}}if( flag != 1 )return false;}return true;}bool same( item a, item b[] /* b is my_item*/ ){int flag;for( int x = 0; x <= id; x++ ){if( a.num == b[x].num ){if( cmp( a, b[x] ) )return true;}}return false;}void add( int i, int j, item temp[], item current ){int s = current.gram[j].s_pos;int l = current.gram[j].s_len;if( current.gram[j].content[s] == Symbol[i] ){temp[i].gram[temp[i].num] = current.gram[j];temp[i].gram[temp[i].num].s_pos++;s = temp[i].gram[temp[i].num].s_pos;if( s < l )temp[i].next[local(temp[i].gram[temp[i].num].content[s])] = HAVE_LIST;temp[i].num++;}}bool can_closure( item temp ){for( int i = 0; i < temp.num; i++ ){char s = temp.gram[i].content[temp.gram[i].s_pos];if( is_nterminal(s) )return true;}return false; }void closure( item & temp ){int f;//while( can_closure( temp ) )//{f++;for( int i = 0; i < temp.num; i++ )// closure {if(temp.gram[i].s_pos < temp.gram[i].s_len && is_nterminal(temp.gram[i].content[temp.gram[i].s_pos]) != -1 ){char x = temp.gram[i].content[temp.gram[i].s_pos];if( is_nterminal(x) ){for( int h = 0; h < my_item[0].num; h++ ){if( my_item[0].gram[h].content[0] == x && do_not_have( h, temp ) ){strcpy( temp.gram[temp.num].content, my_item[0].gram[h].content );temp.gram[temp.num].s_pos = 3;temp.gram[temp.num].s_len = strlen( temp.gram[temp.num].content);temp.num++;temp.next[local(x)] = HAVE_LIST;}}}}}  //}}bool do_not_have( int x, item temp ){for( int i = 0; i < temp.num; i++ ){if( !strcmp( my_item[0].gram[x].content, temp.gram[i].content) && my_item[0].gram[x].s_pos == temp.gram[i].s_pos )return false;}return true; }void init( item temp[], int num ){for( int i = 0; i < num; i++ ){temp[i].id = -1;temp[i].num = 0;for( int j = 0; j < 200; j ++ ){temp[i].next[j] = -1;strcpy( temp[i].gram[j].content, "\0" );temp[i].gram[j].s_pos = 3;temp[i].gram[j].s_len = -1;}}}void input(){char temp[30], i = 0;printf( "please input terminal-Symbol\n" );          scanf( "%s", terSymbol );      printf( "plaese input no-terminal-Symbol\n" );          scanf( "%s", nterSymbol );      vtnum = strlen( terSymbol );      vnnum = strlen( nterSymbol ); strcpy( Symbol, nterSymbol );strcat( Symbol, terSymbol );vnum = vtnum + vnnum; printf( "please input the grammer(end with #):\n" );i = 0;while( scanf( "%s", temp ) && temp[0] != '#' ){strcpy( my_item[id].gram[i].content, temp );my_item[id].gram[i].s_len = strlen(temp);my_item[id].gram[i].s_pos = 3;i++;}my_item[id].num = i;}int local( char x ){for( int i = 0; i < vnum; i++ )if( Symbol[i] == x )return i; return -1;}int is_nterminal( char ch ){for( int i = 0; i < vnnum; i++ )if( ch == nterSymbol[i] )return i;return -1;}