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문제 :https://www.acmicpc.net/problem/2688 접근 : - n = 1, dp[1] = 10, before = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10} - n = 2, dp[2] = 10 - 0 + 10 - 1 + 9 - 1 + · · · + 2 - 1 , before = {0, 10, 9 , 8, 7, 6, 5, 4, 3, 2, 1} - n = 3, dp[3] = 55 - 0 + 55 - 10 + 45 - 9 + · · · + 2 - 1, before = {0, 55, 45, 36, 28, 21, 15, 10, 6, 3, 1} 즉 dp[n] = dp[n-1] - before[0] + (dp[n-1] - before[0]) - before[1]..