Given two integer arrays arr[] and cost[] of size** N**, the task is to make all adjacent elements distinct at minimum cost. cost[i] denotes the cost to increment ith element by 1.

Examples:

Input:_ arr[] = {2, 2, 3}, cost[] = {4, 1, 5}_

Output:_ 2_

Explanation:

The second element has minimum increment cost. Hence, increase the cost of the second element twice.

Therefore the resultant array: {2, 4, 3}

Input:_ arr[] = {1, 2, 3}, cost[] = {7, 8, 3}_

Output:_ 0_

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach:

• We can observe that there an element might need to be increased maximum twice.
• This problem can be solved using Dynamic Programming.
• Create a DP-table dp[][], where rows represent the elements, and columns represent the increment.
• dp[i][j] is the minimum cost required to make ith element distinct from its adjacent elements using j increments.
• The value of dp[i][j] can be calculated as:

dp[i][j] = j * cost[i] + (minimum from previous element if both elements are different)

#arrays #dynamic programming #greedy