GUPTA MECHANICAL

IN THIS WEBSITE I CAN TELL ALL ABOUT TECH. TIPS AND TRICKS APP REVIEWS AND UNBOXINGS ALSO TECH. NEWS .............

Wednesday 24 August 2022

[Solution] Rocket Pack CodeChef Solution 2022



Problem

Chef's robot starts from the coordinate (0, 0) and wishes to reach to the coordinate (N, M).

The initial energy of the robot is 0. There are K batteries kept at some of the coordinates such that picking up the i^{th} battery costs C_i units, and, on picking the i^{th} battery, the current energy of the robot becomes E_i.

Note that one coordinate can have multiple batteries but the robot can pick at most one battery out of those.

For example, if the robot reaches a certain coordinate with energy A and there are two batteries with energy B_1 and B_2 on that coordinate, the robot may choose at most one battery out of these. On choosing the first battery, the energy of the robot becomes B_1 (not A+B_1).

The robot can walk in all the four directions as follows:

  • Move up: Moving from coordinate (X, Y) to (X, Y+1), the robot loses 1 unit of energy.
  • Move down: Moving from coordinate (X, Y) to (X, Y-1), the robot gains 1 unit of energy.
  • Move right: Moving from coordinate (X, Y) to (X+1, Y), the robot loses 1 unit of energy.
  • Move left: Moving from coordinate (X, Y) to (X-1, Y), the robot gains 1 unit of energy.

Find the minimum cost to reach (N, M) if the robot maintains a non-negative energy throughout the journey (including the destination).

Solution Click Below:-  👉CLICK HERE👈
👇👇👇👇👇

Input Format

  • The first line of input contains a single integer T, the number of test cases. The description of the test cases follows.
  • Each test cases consists of two lines of input.
    • The first line contains three positive integers N, M, and K, the coordinates of the destination and the number of batteries.
    • Next K lines have four space-separated integers each: X_i, Y_i, C_i, E_i. The i^{th} line indicates that the coordinate (X_i, Y_i) has a battery with cost C_i and energy E_i.
  • The input data guarantees that the robot can reach the destination.

Output Format

For each test case, output a single integer, the minimum cost from (0,0) to (N, M).


Explanation:

Test case 1: Use the first battery with cost 10. Thus, at coordinate (0, 0), the energy of the robot becomes 10 units. The robot can traverse the path :(0,0) - (0, 1) - \ldots - (0, 5) - (1, 5) - \ldots - (5,5). It can be shown that the robot cannot reach the destination in less than 10 units cost.

Test case 2:

  • Use the 2^{nd} battery: At coordinate (0, 0), robot picks the 2^{nd} battery and the energy of the robot becomes 4 units. The robot can move to coordinate (2, 2) using this energy. On reaching (2, 2), robot's energy is 0.
  • Use the 3^{rd} battery: At coordinate (2, 2), robot picks the 3^{rd} battery and the energy of the robot becomes 1 unit. The robot can move from (2, 2) to (2, 1) and gain 1 unit of energy. Thus, it has 2 units of energy now. It can now move from (2, 1) to (4, 1) using this energy.
  • Use the 4^{th} battery: At coordinate (4, 1), robot picks the 4^{th} battery and the energy of the robot becomes 5 units. The robot can now move from (4, 1) to (5, 5).

No comments:

Post a Comment