C + + implementation of Evaluation algorithm for double stack arithmetic expression of Dijkstra

1#include <iostream>2#include <string>3 using namespacestd;4 5Template<typename t>6 classStack7 {8 Private:9T stack[ -];Ten     inti =0; One  Public: AStack () =default; -  - T pop () the     { -         if(i = =-1) -         { -cout <<"stack is empty! "<<Endl; +             return 0; -         } +  AT top = stack[i-1]; at--i; -         returntop; -     } -  -     voidpush (T num) -     { in++i; -Stack[i-1] =num; to     } +  -     voidClear () the     { *          for(intj =0; J < -; ++j) $         {Panax NotoginsengT[J] =0; -         } the     } + }; A  the intMain () + { -stack<string>ops; $stack<Double>num; $     stringstr; -  -Std::cout <<"Please enter a formula:"<<Endl; thecout <<"Note: Each character putting, please separate the sub-expression, please enclose in parentheses"<<Endl; -cout <<"The character E represents the end"<<Endl;Wuyi      while(true) the     { -CIN >>str; Wu              if(str = ="(")Continue; -         Else if(str = ="+") Ops.push (str); About         Else if(str = ="-") Ops.push (str); $         Else if(str = ="*") Ops.push (str); -         Else if(str = ="/") Ops.push (str); -         Else if(str = =")") -         { A             stringOP =Ops.pop (); +             Doubleval =Num.pop (); the             if(OP = ="+") val = num.pop () +Val; -             if(OP = ="-") val = Num.pop ()-Val; $             if(OP = ="*") val = Num.pop () *Val; the             if(OP = ="/") val = Num.pop ()/Val; the Num.push (val); the         } the  -         Else if(str! ="E") in         { the             Doubleval =Stod (str); the Num.push (val); About         } the               the         if(str = ="E") the         { +              Break; -         } the     }Bayi  thecout <<"The result is:"; thecout << Num.pop () <<Endl; -  -     return 0; the}

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Dijkstra binary arithmetic expression evaluation algorithm C + + implementation