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EXPLANATION

It is easy to see that in order to make the least number of stops, one should cover as much distance as possible each time. We can compute this in linear time, by maintaining two pointers p1 and p2 such that a[p2] - a[p1] <= M, but a[p2+1] - a[p1] > M. We can decrement p1 and adjust p2 accordingly.

Thus we get get for each point i, dp[i], which is the minimum number of steps to reach the destination from location i. To count the number of ways, we have dp[i] = sum dp[j], such that dp[j] = dp[i+1], and a[j] - a[i] <= M. We can easily compute the dp[] array in linear time as well.

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asked 28 Nov '12, 18:38

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So if the input is 5 6 0 4 5 6 10 Would the array dp={4,2,2,1,1}? or array dp={3,1,1,1}? In the above explanation: "Thus we get get for each point i, dp[i], which is the minimum number of steps to reach the destination from location i."

Does dp[i] show us the minimum number of steps from i to destination or the number of ways from i to destination?

(25 Dec '12, 14:13) jaskaran_13★

I seem to have the same problem as @jaskaran_1

(27 Jan '13, 23:22) aman054★
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question asked: 28 Nov '12, 18:38

question was seen: 2,981 times

last updated: 27 Jan '13, 23:22