c++實(shí)現(xiàn)的完整功能計(jì)算器

1、些說(shuō)明:本程序支持基本的四則運(yùn)算，三角函數(shù)運(yùn)算（ sin ， cos ， tan ），指數(shù)運(yùn)算，以及對(duì)數(shù)運(yùn)算（ lg ， ln ， log ），取模運(yùn)算，同時(shí)還支持括號(hào)！主函數(shù)流程：輸入運(yùn)算式子 -> 判斷是否有異常字符 -> 對(duì)式子進(jìn)行處理以便于計(jì)算->調(diào)用計(jì)算沒(méi)有括號(hào)的式子的函數(shù)去除括號(hào)，即先計(jì)算括號(hào)里的子式-> 最后得到?jīng)]有括號(hào)的式子， 在調(diào)用函數(shù)計(jì)算得到結(jié)果。值得注意的是輸入運(yùn)算式子時(shí)， 必 須寫(xiě)成 alogb ， 必 須寫(xiě)成 pi ，三角函數(shù)若不是tanN形式的話，要加上括號(hào)如tan （a+b）,這是由于控 制臺(tái)輸入的限制和為了輸入后便于處理。子函數(shù)流程：從運(yùn)

2、算式子中讀出數(shù)字和字符， 分別存于一個(gè)隊(duì)列中 -> 按順序取出數(shù)字與字符， 進(jìn)行乘方運(yùn)算， 其他的再一次放回隊(duì)列中 -> 依次再取出進(jìn)行三角函數(shù)和對(duì)數(shù)的運(yùn)算， 其他依次放回 -> 再依次取出進(jìn)行乘除和取模運(yùn)算， 其他依次放回 -> 現(xiàn)在只剩下加減運(yùn)算， 依次取出計(jì)算，得到最后的結(jié)果。關(guān)鍵技術(shù)：一、c+的sstream流的運(yùn)用，可以從中分別讀出運(yùn)算式子的數(shù)字與字符還有去除括號(hào)時(shí)將未處理字符（即非括號(hào)內(nèi)的字符）以及括號(hào)內(nèi)的子式處理結(jié)果輸出到流中，便于迭代去除括號(hào)。2、 對(duì)沒(méi)括號(hào)的式子進(jìn)行分級(jí)處理。3、 將式子的字符以及數(shù)字分開(kāi)處理。源代碼如下：#include<ios

3、tream> #include<sstream> #include<string> #include<cmath> #include<queue>#define pi 3.141592654 double calculate( std:string);int main()/輸入式子，存于s 中std:string s;std:getline(std:cin, s);/拋出異常try/判斷是否有異常字符const std:string jubge = "1234567890 tan sin cos +-*/八(|) log ln l

4、g sqrt pi!"for (const auto &i : s)if (jubge. find(i) = -1)throw 1;/ 拋出異常/將三角函數(shù)名化為數(shù)字與&字符，便于識(shí)別和計(jì)算以及將對(duì)數(shù)函數(shù)以及階乘以及開(kāi)方將pi/?；癁閿?shù)字size_t n = 0;while (n = s. find("sin") != -1)s. replace(n, 3, "1&");while (n = s. find("cos") != -1)s. replace(n, 3, "2&"

5、;);while (n = s. find("tan") != -1)s. replace(n, 3, "3&");while (n = s. find("ln") != -1)s. replace(n, 2, "4&");while (n = s. find("lg") != -1)s. replace(n, 2, "5&");while (n = s. find("sqrt") != -1)s. replace(n, 4, &q

6、uot;6&");while (n = s. find("log") != -1)s. replace(n, 3, "");while (n = s. find("!") != -1)s. replace(n, 1, "$7");while (n = s. find("pi") != -1)s. replace(n, 2, std:to_string(pi);/去除括號(hào)while (s. find("(") != -1|s. find(")&quo

7、t;)!=-1)std:ostringstream uout;/ 存儲(chǔ)未處理字符auto left = s. begin();/記錄左括號(hào)位置auto right = s. begin();/記錄右括號(hào)位置while (right != s. end()/ 處理最里層括號(hào)里的字符if (*right = '(')if (*left = '(')for (auto i = left; i != right; +i)uout << *i;left = right;else if (*right = ')')if (*left != 

8、9;(') throw 2;/ 拋出異常uout << calculate( std:string(left + 1, right);break;else if (*left != '(')uout << *right;else;+right;if (*left = '('&&right = s. end() throw 3;/ 拋出異常for (auto i = right + 1; i != s. end(); +i)/ 輸出剩余未處理符uout << *i;s = uout. str();/將處理

9、一對(duì)括號(hào)后的字符串賦給s/計(jì)算最后結(jié)果 double result = calculate(s);/輸出結(jié)果std:cout << result << std:endl;catch (int e)/ 捕獲并處理異常using std:cout;using std:endl;cout << "Input Error!" << endl;switch (e)case 1: cout << "式子中有異常字符！ " << endl; break;case 2: cout <<

10、"缺左括號(hào)！" << endl; break;case 3: cout << "缺右括號(hào)！" << endl; break;case 4: cout << "運(yùn)算符相連或?qū)?shù)等復(fù)活寫(xiě)錯(cuò)！ " << endl;break;default:;system("pause");return 0;double calculate( std:string s)/將數(shù)字和運(yùn)算符分別裝入雙向隊(duì)列和隊(duì)列適配器中std:deque<double> number;s

11、td:queue<char> symbol;std:istringstream uin(s);symbol. push('+');/ 添加加號(hào)為第一個(gè)運(yùn)算符double tpn; char tpc;while (uin >> tpn >> tpc)number. push_back(tpn), symbol. push(tpc);if (!uin. eof() throw 4;/ 拋出異常number. push_back(tpn);/ 添加最后一個(gè)數(shù)字/計(jì)算乘方for (int i = 0, n = number. size(); i &l

12、t; n; +i)tpc = symbol. front(); symbol. pop();取出運(yùn)算符tpn = number. front(); number. pop_front();取出數(shù)字if (tpc ='八')計(jì)算乘方double temp = number. back();number. back() = pow(temp, tpn);elsesymbol. push(tpc);/ 放回隊(duì)列，置于最后精品資料number. push_back(tpn);/ 放回隊(duì)列，置于最后/計(jì)算三角函數(shù)以及對(duì)數(shù) for (int i = 0, n = number. size(

13、); i < n; +i)tpc = symbol. front(); symbol. pop();取出運(yùn)算符tpn = number. front(); number. pop_front();取出數(shù)字if (tpc = '&')/ 計(jì)算乘方以及對(duì)數(shù)switch (int(number. back()case 1:number. back() case 2:number. back() case 3:number. back() case 4:number. back() case 5:number. back() case 6:number. back() d

14、efault:;= sin(tpn); break;= cos(tpn); break;= tan(tpn); break;= log(tpn); break;= log10(tpn); break;= sqrt(tpn); break;else if (tpc = '')/ 計(jì)算對(duì)數(shù)double temp = number. back();number. back() = log(tpn) / log(temp);else if (tpc = '$')/ 計(jì)算階乘int n = number. back();number. back() = 1;for (in

15、t i = 1; i <= n; +i) number. back() *= i;elsesymbol. push(tpc);/ 放回隊(duì)列，置于最后number. push_back(tpn);/ 放回隊(duì)列，置于最后/計(jì)算乘除以及取模運(yùn)算for (int i = 0, n = number. size(); i < n; +i)tpc = symbol. front(); symbol. pop();取出運(yùn)算符tpn = number. front(); number. pop_front();取出數(shù)字if (tpc = '+' | tpc = '-')symbol. push(tpc);number. push_back(tpn);else if (tpc = '*')number. back() *= tpn;/ 計(jì)算乘else if (tpc = '/')number. back() /= tpn;/ 計(jì)算除else/取模運(yùn)算double temp = number. back();temp = int(temp) % int(tpn);number. back() = temp;/計(jì)算加減得出結(jié)果double resu