Solution 4 for Scaler Topics Fortnightly Contest - 4
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DSA Problem Solving for Interviews using Java
by Jitender Punia
1000
4.9
This article is part of the Scaler Topics Fortnightly Contest - 4.
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Solution Approach
- Since we need to find the minimum time required to reach city A, we can modify dijktras to get the required time.
- For each city we maintain the following two states:
- Minimum time required to reach city i, such that the parity of potions used is 0. We store it in state dist[i][0].
- Minimum time required to reach city i, such that the parity of potions used is 1. We store it in state dist[i][1].
- So we can perform simple dijktras using the two states i.e., dist[i][0] and dist[i][1]. The answer would be stored at dist[A][0].
Time complexity: O(V + ElogV), where V is the number of vertices and E is the number of edges.
Extra memory complexity: O(V), for storing vertices while performing dijktras.
C++ Implementation
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