Create Operator_precedence_using_Stack_ADT.c

Author: santhosh-programmer

Operator_precedence_using_Stack_ADT.c

@@ -0,0 +1,58 @@
+// Given an arithmetic expression, find the operator with highest priority using stack.
+
+//  (consider only basic arithmetic operators)
+
+#include<stdio.h>
+#include<string.h>
+char s[20];
+int top=-1;
+int pri(char c)
+{
+    switch(c)
+    {
+        case '+':
+        case '-':return 1;
+                 break;
+        case '*':
+        case '/':return 2;
+                 break;
+        default: return 0;
+    }
+}
+void push(char c)
+{
+    top++;
+    s[top]=c;
+}
+char pop()
+{
+    int a=top;
+    top--;
+    return s[a];
+}
+int main()
+{
+    char str[20],temp;
+    scanf("%[^\n]s",str);
+    for(int i=0;i<strlen(str);i++)
+    {
+        if(str[i]=='+'||str[i]=='-'||str[i]=='*'||str[i]=='/')
+        {
+            if(top==-1)
+            push(str[i]);
+            else
+            {
+                if(pri(s[top])>=pri(str[i]))
+                {
+                    temp=pop();
+                    push(str[i]);
+                    push(temp);
+                }
+                else
+                push(str[i]);
+            }
+        }
+    }
+    printf("%c",pop());
+    return 0;
+}