1、實 驗 報 告（ / 學年 第 一 學期）課程名稱離散數學實驗名稱利用真值表法求主析取范式及主合取范式的實現實驗時間年月日指導單位指導教師學生姓名班級學號學院(系)專 業 實 驗 報 告實驗名稱利用真值表法求主析取范式及主合取范式的實現指導教師實驗類型上機實驗學時4實驗時間一、 實驗目的和要求能夠列出合式公式的真值表并給出相應主析取范式和主合取范式。二、實驗環境(實驗設備)硬件:PC機。軟件:Code:Blocks （C+ ）三、實驗原理及內容 內容：編程實現用真值表法求任意含三個以內變量的合式公式的主析取范式和主合取范式。 原理：首先讀入變元個數，然后讀入合式公式，用堆棧的知識將中綴表達式轉

2、化為后綴表達式，調用否定、析取、合取、條件、雙條件的函數計算P、Q、R取不同真值時合式公式的真值，然后輸出真值表，調用計算主析取范式和主合取范式的函數并輸出。 程序：#include<iostream>#include<string>#include<conio.h>#include<windows.h>using namespace std;string OriginalForm; /原式string Hequ; /主合取范式string Xiqu; /主析取范式class SeqStack/建立一個堆棧，利用將中綴表達式轉為后綴表達式publ

3、ic: SeqStack(int mSize); SeqStack(); char Top(); bool Push(char x); bool Pop();private: char *st; int top; int maxtop;SeqStack:SeqStack(int mSize) maxtop = mSize - 1; top = -1; st = new charmSize;SeqStack:SeqStack() deletest;char SeqStack:Top() return sttop;bool SeqStack:Push(char x) if(top = maxtop

4、) return false; st+top = x; return true;bool SeqStack:Pop() if(top = -1) return false; top-; return true;int p, q, r, s, t, u;int a, b, result;int v =0;int number;/用number表示變元的個數SeqStack stack(200);void Not() /否定 a = stack.Top(); stack.Pop(); result = a = 1 ? 0 : 1; stack.Push(result);void Or() /析取

5、result = a + b; result = result > 1 ? 1 : result; stack.Push(result);void And() /合取 result = a * b; stack.Push(result);void If() /條件,b->a result = (b = 1 && a = 0) ? 0 : 1; stack.Push(result);void Doubleif() /雙條件 result = (b = a) ? 1 : 0; stack.Push(result);bool CanIn(char out)/優先級的判斷

6、char in = stack.Top(); int i, o; switch(in) case '#':i = 0; break; case '(':i = 1; break; case '-':i = 3; break; case '>':i = 5; break; case '|':i = 7; break; case '&':i = 9; break; case '!':i = 11; break; case ')':i = 12; break;

7、 switch(out) case '#':o = 0; break; case '(':o = 12; break; case '-':o = 2; break; case '>':o = 4; break; case '|':o = 6; break; case '&':o = 8; break; case '!':o = 10; break; case ')':o = 1; break; if(i < o) return true; else

8、 return false;void InfixToPostfix()/中綴表達式轉后綴表達式 string tmp = "" stack.Push('#'); for(int i = 0; (unsigned)i <OriginalForm.length(); i+) if(OriginalFormi = 'P' | OriginalFormi = 'Q' |OriginalFormi = 'R' | OriginalFormi = 'S' | OriginalFormi = '

9、T' | OriginalFormi = 'U') tmp=tmp+OriginalFormi; continue; if(CanIn(OriginalFormi) stack.Push(OriginalFormi); else if(OriginalFormi = ')') while(stack.Top() != '(') tmp = tmp + stack.Top(); stack.Pop(); stack.Pop(); else do tmp = tmp + stack.Top(); stack.Pop(); while(!Can

10、In(OriginalFormi); stack.Push(OriginalFormi); while(stack.Top() != '#') tmp = tmp + stack.Top(); stack.Pop(); stack.Pop(); OriginalForm = tmp;void Calculate()/計算主析取范式和主合取范式的函數 if(number = 3) for(int i = 0; (unsigned)i <OriginalForm.length(); i+) if(OriginalFormi = 'P' | OriginalFo

11、rmi = 'Q'| OriginalFormi = 'R') v = OriginalFormi = 'P' ? p : OriginalFormi= 'Q' ? q : r; stack.Push(v); continue; if(OriginalFormi != '!') a = stack.Top(); stack.Pop(); b = stack.Top(); stack.Pop(); switch(OriginalFormi) case '-':Doubleif(); break; ca

12、se '>':If(); break; case '|':Or(); break; case '&':And(); break; case '!':Not(); break; if(number = 2) for(int i = 0; (unsigned)i <OriginalForm.length(); i+) if(OriginalFormi = 'P' | OriginalFormi = 'Q') v = OriginalFormi = 'P' ? p :

13、q; stack.Push(v); continue; if(OriginalFormi != '!') a = stack.Top(); stack.Pop(); b = stack.Top(); stack.Pop(); switch(OriginalFormi) case '-':Doubleif(); break; case '>':If(); break; case '|':Or(); break; case '&':And(); break; case '!':Not();

14、 break; void Print() if(number = 3) cout << "Pt" <<"Qt" << "Rt" << "Z" << endl; for(p = 1; p >= 0; p-) for(q = 1; q >= 0; q-) for(r = 1; r >= 0; r-) Calculate(); if(result = 1) Xiqu =Xiqu +"(" + (p = 1 ? "P

15、" : "!P") + "&" +(q = 1 ? "Q" : "!Q") + "&" + (r = 1 ?"R" : "!R") + ")" + " | " else Hequ = Hequ +"(" + (p = 0 ? "P" : "!P") + "|" + (q= 0 ? "Q" :

16、"!Q") + "|" + (r = 0 ?"R" : "!R") + ")" + " & " cout << p <<"t" << q << "t" << r <<"t" << result << endl; if(number = 2) cout << "Pt" <<

17、"Qt" << "Z" << endl; for(p = 1; p >= 0; p-) for(q = 1; q >= 0; q-) Calculate(); if(result = 1) Xiqu =Xiqu + "("+ (p = 1 ? "P" : "!P") + "&" + (q = 1 ?"Q" : "!Q") + ")" + " | " el

18、se Hequ = Hequ + "(" + (p =0 ? "P" : "!P") + "|" + (q = 0 ? "Q" :"!Q") + ")" + " & " cout << p <<"t" << q << "t" << result << endl; cout<<endl; if(Xiqu.le

19、ngth() != 0) Xiqu.erase(Xiqu.length() - 2); if(Hequ.length() != 0) Hequ.erase(Hequ.length() - 2);cout << "主析取范式："<<Xiqu << endl << endl; cout << "主合取范式：" << Hequ << endl << endl;int main()int flag=1; while(flag=1) SetConsoleTextAttr

20、ibute(GetStdHandle (STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY |FOREGROUND_GREEN|FOREGROUND_BLUE); /設置綠色和藍色相加(即青色) system("cls");/清屏 cout<<"-"<<endl; cout <<" 歡迎使用！"<<endl<<endl; cout << " ! 表示否定" << endl<<endl; cou

21、t << " | 表示析取" << endl<<endl; cout << " & 表示合取" << endl<<endl; cout << " > 表示條件" << endl<<endl; cout << " - 表示雙條件" << endl; cout<<"-"<<endl; cout <<endl<< " 輸入你的變元數目:" cin >> number;cout<<" 請輸入合式公式：" switch(number) case 2:cout << endl <<" 變元請用P、Q表示&