added problem of stack

Author: muskanmi

Stack/Maximumpeople.java

@@ -0,0 +1,76 @@
+package Stack;
+
+public class Maximumpeople {
+
+    public static int leftindex(int[] heights, int idx,
+                              int n)
+  {
+ 
+    int h = heights[idx];
+    for (int i = idx - 1; i >= 0; i--) {
+ 
+      // If height of person i is
+      // greater than or equal to
+      // current person of height h
+      // then the current person(idx)
+      // cannot see him
+      if (heights[i] >= h)
+        return i;
+    }
+    // If a person can see all other people
+    // who are standing on his left
+    return -1;
+  }
+
+    public static int rightindex(int[] heights, int idx,
+    int n)
+{
+int h = heights[idx];
+for (int i = idx + 1; i < n; i++) {
+
+// If height of person i is
+// greater than or equal to
+// current person of height h
+// then the current person(idx)
+// cannot see him
+if (heights[i] >= h)
+return i;
+}
+
+// If a person can see all other people
+// who are standing on his right
+return n;
+}
+
+    public static int max_people(int[] heights, int n)
+  {
+ 
+    // Ans stores the maximum of people
+    // a person can see
+    int ans = 0;
+    for (int i = 0; i < n; i++) {
+ 
+      // Leftptr stores the leftmost index
+      // of the person which
+      // the current person cannot see
+      int leftptr = leftindex(heights, i, n);
+ 
+      // Rightptr stores the rightmost index
+      // of the person which
+      // the current person cannot see
+      int rightptr = rightindex(heights, i, n);
+ 
+      // Maximum number of people
+      // a person can see
+      ans = Math.max(ans, rightptr - leftptr - 1);
+    }
+    return ans;
+  }
+    public static void main(String[] args) {
+        int N = 7;
+    int[] heights = new int[] { 6, 2, 5, 4, 5, 1, 6 };
+ 
+    // Function call
+    System.out.println(max_people(heights, N));
+    }
+}