Introduction to Microservice Architecture Using SpringBoot - Part 1

 Write a C Program for Evaluation of Postfix Expression

 #include<stdio.h>  
 #include<stdlib.h>  
 #include<math.h>  
 #define max 20  
 struct stack  
 {  
      float value[max];  
      int top;  
 };  
 struct stack stk;  
 int isFull()  
 {  
      if(stk.top==max-1)  
           return 1;  
      return 0;  
 }  
 int isEmpty()  
 {  
      if(stk.top==-1)  
           return 1;  
      return 0;  
 }  
 int push(float key)  
 {  
      if(isFull())  
           return -1;  
      stk.value[++stk.top]=key;  
      return stk.top;  
 }  
 float pop()  
 {  
      if(isEmpty())  
           return -1;  
      return stk.value[stk.top--];  
 }  
 float postfixEvaluation(char postfix[], float value[])  
 {  
  int i=0;  
  char ch;  
  float op1, op2;  
  while(postfix[i]!=NULL)   
  {  
   ch = postfix[i];  
   if((ch>=65 && ch<=90) || (ch>=97 && ch<=122))  
           {  
               push(value[i]);  
        }  
   else  
   {  
    op2 = pop();  
    op1 = pop();  
    switch(ch) {  
     case '+': push(op1+op2);  
           break;  
     case '-': push(op1-op2);  
           break;  
           case '*': push(op1*op2);  
           break;  
           case '/': push(op1/op2);  
           break;  
           case '^': push(pow(op1,op2));  
           break;  
    }  
   }  
   i++;  
  }  
  return pop();  
 }  
 int main()   
 {  
  char postfix[20], ch;  
  float value[20], result;  
  int i=0;  
  printf("ENTER A VALID POSTFIX EXPRESSION = ");  
  gets(postfix);  
  while(postfix[i]!='\0')  
  {   
   ch = postfix[i];  
   if((ch>=65 && ch<=90) || (ch>=97 && ch<=122))  
      {  
     printf("\nENTER THE VALUE OF %c =",ch);  
     scanf("%f",&value[i]);  
   }  
   i++;  
  }  
  result = postfixEvaluation(postfix, value);  
  printf("\nRESULT = %f", result);  
  return 0;  
 }  

OUTPUT :