#include #include #include using namespace std; #define SIZE 50 char s[SIZE]; int top=-1; void push(char elem) {

s[++top]=elem;include

} char pop() { return(s[top--]); } int pr(char elem) { switch(elem) { case '#':return 0; case '(':return 1; case '+': case '-':return 2; case '*': case '/':return 3; } } int main() { char infx[50],postfx[50],ch,elem; int i=0,k=0; cout<<"\nEnter the infix Expression:"; cin>>infx; push('#'); while((ch=infx[i++])!='\0') { if(ch=='(') push(ch); else if(isalnum(ch)) postfx[k++]=ch; else if(ch==')') { while(s[top]!='(') postfx[k++]=pop(); elem=pop(); } else{ while(pr(s[top])>=pr(ch)) postfx[k++]=pop(); push(ch); } } while(s[top]!='#') postfx[k++]=pop(); postfx[k]='\0'; cout<<"\nPostfix Expression:\n"<<postfx; return 0; }