Merge pull request #42 from namantiwari2002/main

Added several JavaScript programs

Javascript/armstrong_no.js

@@ -0,0 +1,24 @@
+
+// Program to chech whether is a number is armstrong number or not in javascript
+
+function armstrong(num){
+
+    var temp=num;
+    var arm = 0;
+    while(temp>0)
+    {
+        var a=temp%10;
+        temp=parseInt(temp/10);
+        arm=arm+a*a*a;
+    }
+
+    if(arm == num)return true;
+
+    return false;
+
+}
+
+console.log(armstrong(370));
+
+//Output
+// true

Javascript/fibonacci.js

@@ -1,6 +1,16 @@
 // Fibonacci sequence generator in JavaScript 
 
 function fibonacci(n) {
+    let array = [];
+
+    array[0] = 0;
+    array[1] = 1;
+
+    for (let i = 2; i < n; i++) {
+      array[i] = array[i - 2] + array[i - 1];
+    }
+
+    return array;
 
 }
 

Javascript/infixtopostfix.js

@@ -1,9 +1,63 @@
 // Infix to Postfix Conversion using Stack in JavaScript
 
-function infixToPostfix(str) {
-    // your code here
+function precedence (c) {
+    if (c == '^') {
+        return 3;
+    }
+    else if (c == '/' || c == '*') {
+        return 2;
+    }
+    else if (c == '+' || c == '-') {
+        return 1;
+    }
+    else {
+        return 0;
+    }
 }
 
+function isOperand (c) {
+	if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9')) {
+		return 1;
+	}
+	return 0;
+}
+
+function infixToPostfix(s){
+    let st = []; 
+    let postFix = "";
+
+    for (let i = 0; i < s.length; i++) {
+        if (isOperand(s[i])) {
+            postFix += s[i];
+        }
+        else if (s[i] == '(') {
+            st.push('(');
+        }
+        else if (s[i] == ')') {
+            while (st[st.length - 1] != '(') {
+                postFix += st[st.length - 1];
+                st.pop();
+            }
+            st.pop();
+        }
+        else {
+            while (st.length != 0 && precedence(s[i]) <= precedence(st[st.length - 1])) {
+                postFix += st[st.length - 1];
+                st.pop();
+            }
+            st.push(s[i]);
+        }
+    }
+
+    while (st.length != 0) {
+        postFix += st[st.length - 1];
+        st.pop();
+    }
+    return postFix;
+}
+
+
+
 console.log(infixToPostfix("a+b*(c^d-e)^(f+g*h)-i"));
 
 // Output: