Submission #379317

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
379317	2021-03-18T01:23:19 Z	ChrisT	Salesman (IOI09_salesman)	C++17	100 / 100	888 ms	36460 KB

salesman

#include<bits/stdc++.h>
using namespace std;
const int MN = 5e5 + 5;
struct Seg {
	int tree[MN << 1]; int n;
	Seg() {n = MN; memset(tree,-0x3f,sizeof tree);}
	void update (int i, int v) {
		for (tree[i += n-1] = v; i > 1; i >>= 1)
			tree[i>>1] = max(tree[i],tree[i^1]);
	}
	int query (int l, int r) {
		int ret = -1e9;
		for (l += n-1, r += n; l < r; l >>= 1, r >>= 1) {
			if (l&1) ret = max(ret,tree[l++]);
			if (r&1) ret = max(ret,tree[--r]);
		}
		return ret;
	}
} segL, segR;
vector<array<int,2>> atT[MN];
int main () {
	int n,u,d,s;
	scanf ("%d %d %d %d",&n,&u,&d,&s);
	while (n--) {
		int t,l,m; scanf ("%d %d %d",&t,&l,&m);
		atT[t].push_back({l,m});
	}
	atT[MN-1].push_back({s,0});
	segL.update(s,d * s); segR.update(s,-u*s);
	for (int t = 1; t < MN; t++) if (!atT[t].empty()) {
		int m = (int)atT[t].size();
		vector<int> dp1(m), dp2(m);
		sort(atT[t].begin(),atT[t].end());
		for (int i = 0; i < m; i++) {
			auto [l,c] = atT[t][i];
			dp1[i] = max(segL.query(1,l) - d * l + c,segR.query(l,MN) + u * l + c);
			segL.update(l,dp1[i] + d * l); segR.update(l,dp1[i] - u * l);
		}
		for (int i = 0; i < m; i++) segL.update(atT[t][i][0],-1e9), segR.update(atT[t][i][0],-1e9);
		for (int i = m-1; i >= 0; i--) {
			auto [l,c] = atT[t][i];
			dp2[i] = max(segL.query(1,l) - d * l + c,segR.query(l,MN) + u * l + c);
			segL.update(l,dp2[i] + d * l); segR.update(l,dp2[i] - u * l);
		}
		for (int i = 0; i < m; i++) {
			auto [l,c] = atT[t][i];
			segL.update(l,max(dp1[i],dp2[i]) + d * l); segR.update(l,max(dp1[i],dp2[i]) - u * l);
		}
		if (t + 1 == MN) return !printf ("%d\n",dp1[0]);
	}
	return 0;
}

Compilation message

salesman.cpp: In function 'int main()':
salesman.cpp:23:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |  scanf ("%d %d %d %d",&n,&u,&d,&s);
      |  ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
salesman.cpp:25:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   25 |   int t,l,m; scanf ("%d %d %d",&t,&l,&m);
      |              ~~~~~~^~~~~~~~~~~~~~~~~~~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	17 ms	19948 KB	Output is correct
2	Correct	17 ms	19948 KB	Output is correct
3	Correct	18 ms	19948 KB	Output is correct
4	Correct	16 ms	19948 KB	Output is correct
5	Correct	21 ms	19988 KB	Output is correct
6	Correct	49 ms	20844 KB	Output is correct
7	Correct	105 ms	21876 KB	Output is correct
8	Correct	196 ms	23660 KB	Output is correct
9	Correct	270 ms	25196 KB	Output is correct
10	Correct	421 ms	29804 KB	Output is correct
11	Correct	549 ms	29804 KB	Output is correct
12	Correct	710 ms	33132 KB	Output is correct
13	Correct	704 ms	33132 KB	Output is correct
14	Correct	865 ms	36460 KB	Output is correct
15	Correct	714 ms	36460 KB	Output is correct
16	Correct	888 ms	36460 KB	Output is correct
17	Correct	14 ms	19948 KB	Output is correct
18	Correct	17 ms	19948 KB	Output is correct
19	Correct	15 ms	19948 KB	Output is correct
20	Correct	16 ms	19948 KB	Output is correct
21	Correct	16 ms	19948 KB	Output is correct
22	Correct	19 ms	20076 KB	Output is correct
23	Correct	19 ms	20076 KB	Output is correct
24	Correct	19 ms	20076 KB	Output is correct
25	Correct	153 ms	21612 KB	Output is correct
26	Correct	259 ms	22688 KB	Output is correct
27	Correct	436 ms	24416 KB	Output is correct
28	Correct	470 ms	24672 KB	Output is correct
29	Correct	629 ms	25324 KB	Output is correct
30	Correct	595 ms	26080 KB	Output is correct