Longest appointment that can be served with a break in between

Author: sonugiri1043

17-Hard/16-The-Masseuse.cpp

@@ -0,0 +1,73 @@
+/*
+  The Masseuse:
+  A popular masseuse receives a sequence of back-to-back appointment requests and is debating
+  which ones to accept. She needs a 15-minute break between appointments and therefore she cannot
+  accept any adjacent requests. Given a sequence of back-to-back appointment requests (all multiples
+  of 15 minutes, none overlap, and none can be moved), find the optimal (highest total booked minutes)
+  set the masseuse can honor. Return the number of minutes.
+
+  EXAMPLE
+  Input: {30, 15, 60, 75, 45, 15, 15, 45}
+  Output: 180 minutes ({30, 60, 45, 45})
+
+  INPUT: {75, 105, 120, 75, 90, 135}
+  OUTPUT: 330 minutes ({75, 120, 135})
+ */
+
+// g++ 16-The-Masseuse.cpp --std=c++11
+
+#include <iostream>
+#include <vector>
+
+using std::cout;
+using std::endl;
+using std::vector;
+
+int optimalBooking( const vector<int> input ) {
+  int maxBooking=0;
+  vector< int > max( input.size(), 0 );
+  max[0] = input[0];
+  max[1] = input[0] > input[1] ? input[0] : input[1];
+  for( int i = 2; i < input.size(); i++ ) {
+    if( max[i-2] + input[i] > max[ i-1 ] ) {
+      max[ i ] = max[i-2] + input[i];
+    } else {
+      max[i] = max[i-1];
+    }
+    if( max[i] > maxBooking ) {
+      maxBooking = max[i];
+    }   
+  }
+  return maxBooking;
+}
+
+int optimalBookingV2( const vector<int> input ) { 
+  int maxBooking=0;
+  int max;
+  int maxTwoAway = input[0];
+  int maxOneAway = input[0] > input[1] ? input[0] : input[1];
+  for( int i = 2; i < input.size(); i++ ) {
+    if( maxTwoAway + input[i] > maxOneAway ) {
+      max = maxTwoAway + input[i];
+    } else {
+      max = maxOneAway;
+    }
+    maxTwoAway = maxOneAway;
+    maxOneAway = max;
+
+    if( max > maxBooking ) {
+      maxBooking = max;
+    }    
+  }
+  return maxBooking;
+}
+
+int main() {
+  vector<int> input1 = {30, 15, 60, 75, 45, 15, 15, 45};
+  vector<int> input2 = {75, 105, 120, 75, 90, 135};
+  cout<< optimalBooking( input1 ) << endl;
+  cout<< optimalBooking( input2 ) << endl;
+  cout<< optimalBookingV2( input1 ) << endl;
+  cout<< optimalBookingV2( input2 ) << endl;
+  return 0;
+}