rest of the codes

InfixToPosfix.c

@@ -0,0 +1,92 @@
+#include<stdio.h>
+#define MAX 20
+
+typedef enum { lparen, rparen, plus, minus, times, divide, mod, eos, operand } precedence;
+
+precedence stack[30];
+int top = -1;
+char EXPR[MAX];
+
+int isp[] = { 0, 19, 12, 12, 13, 13, 13, 0 };   // in-stack precedence
+int icp[] = { 20, 19, 12, 12, 13, 13, 13, 0 };  // incoming precedence
+
+void push(precedence token)
+{
+    stack[++top] = token;
+}
+
+precedence pop()
+{
+    return stack[top--];
+}
+
+precedence get_token(char *symbol, int *n)
+{
+    *symbol = EXPR[(*n)++];
+    switch (*symbol)
+    {
+        case '(': return lparen;
+        case ')': return rparen;
+        case '+': return plus;
+        case '-': return minus;
+        case '*': return times;
+        case '/': return divide;
+        case '%': return mod;
+        case '\0': return eos;
+        default:  return operand;
+    }
+}
+
+void print_token(precedence token)
+{
+    switch (token)
+    {
+        case plus:   printf("+");  break;
+        case minus:  printf("-");  break;
+        case times:  printf("*");  break;
+        case divide: printf("/");  break;
+        case mod:    printf("%%"); break;
+        default:     break;
+    }
+}
+
+void postfix()
+{
+    char symbol;
+    precedence token;
+    int n = 0;
+
+    top = 0;
+    stack[0] = eos;
+
+    for (token = get_token(&symbol, &n); token != eos; token = get_token(&symbol, &n))
+    {
+        if (token == operand)
+            printf("%c", symbol);
+        else if (token == rparen)
+        {
+            while (stack[top] != lparen)
+                print_token(pop());
+            pop(); // pop '('
+        }
+        else
+        {
+            while (isp[stack[top]] >= icp[token])
+                print_token(pop());
+            push(token);
+        }
+    }
+
+    while ((token = pop()) != eos)
+        print_token(token);
+
+    printf("\n");
+}
+
+int main()
+{
+    printf("\nEnter the infix expression\n");
+    scanf("%s", EXPR);
+    postfix();
+    return 0;
+}