Submission #841392

#	Time	Username	Problem	Language	Result	Execution time	Memory
841392		alex_2008	K blocks (IZhO14_blocks)	C++17	100 / 100	226 ms	41684 KiB

blocks

#include <iostream>
using namespace std;
const int N = 100100, K = 101;
int dp[N][K], a[N], prevv[N], mn[N];
int main() {
	int n, k;
	scanf("%d%d", &n, &k);
	a[0] = 1e6 + 10;
	for (int i = 1; i <= n; i++) {
		scanf("%d", &a[i]);
		int j = i - 1;
		while (a[j] < a[i]) {
			j = prevv[j];
		}
		prevv[i] = j;
	}
	dp[0][1] = 1e9 + 10;
	dp[1][1]  = a[1];
	for (int i = 2; i <= n; i++) {
		dp[i][1] = max(dp[i - 1][1], a[i]);
	}
	for (int j = 2; j <= k; j++) {
		mn[0] = 1e9 + 10;
		for (int i = 1; i <= n; i++) {
			mn[i] = 1e9 + 10;
			int x = i - 1;
			while (x != prevv[i]) {
				mn[i] = min(mn[i], mn[x]);
			    mn[i] = min(mn[i], dp[x][j - 1]);
				x = prevv[x];
			}
			mn[i] = min(mn[i], dp[prevv[i]][j - 1]);
		}
		for (int i = 0; i <= n; i++) {
			if (i < j) dp[i][j] = 1e9 + 10;
			else {
				dp[i][j] = dp[prevv[i]][j];
				dp[i][j] = min(dp[i][j], mn[i] + a[i]);
			}
		}
	}
	printf("%d\n", dp[n][k]);
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:7:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    7 |  scanf("%d%d", &n, &k);
      |  ~~~~~^~~~~~~~~~~~~~~~
blocks.cpp:10:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |   scanf("%d", &a[i]);
      |   ~~~~~^~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 18 / 18
• Subtask 3: 21 / 21
• Subtask 4: 47 / 47