Submission #903898

#	Time	Username	Problem	Language	Result	Execution time	Memory
903898		math_rabbit_1028	Wiring (IOI17_wiring)	C++14	100 / 100	43 ms	8952 KiB

wiring

#include <bits/stdc++.h>
#include "wiring.h"
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

vector<pii> arr;
vector<ll> sum;
vector<ll> dp;
ll min_total_length(vector<int> R, vector<int> B) {
	arr.push_back({0, 0});
	for (int i = 0; i < R.size(); i++) arr.push_back({R[i], 0});
	for (int i = 0; i < B.size(); i++) arr.push_back({B[i], 1});
	sort(arr.begin() + 1, arr.end());
	dp = vector<ll>(arr.size(), 1e18);
	sum = vector<ll>(arr.size(), 0);
	for (int i = 1; i < sum.size(); i++) sum[i] = sum[i - 1] + arr[i].first;

	dp[0] = 0;
	int a, b, last, i = 1;
	while (arr[i].second == arr[i+1].second) i++;
	b = i;
	//for (int j = 1; j <= i; j++) dp[j] = dp[j-1] + arr[b+1].first - arr[j].first;
	for (i++; i < arr.size(); i++) {
		if (arr[i].second != arr[i-1].second) {
			a = b;
			b = 0;
			last = arr[i-1].first;
			for (int j = i-a; j < i; j++) {
				dp[j] = min(dp[j], dp[j-1] + arr[i].first - arr[j].first);
			}
		}
		b++;
		if (b <= a) {
			dp[i] = min(dp[i], dp[i-1] + arr[i].first - last);
			dp[i] = min(dp[i], dp[i-2*b] + (sum[i] - sum[i-b]) - (sum[i-b] - sum[i-2*b]));
		}
		else {
			dp[i] = min(dp[i], dp[i-1] + arr[i].first - last);
		}
	}

	return dp[arr.size()-1];
}

Compilation message (stderr)

wiring.cpp: In function 'll min_total_length(std::vector<int>, std::vector<int>)':
wiring.cpp:12:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |  for (int i = 0; i < R.size(); i++) arr.push_back({R[i], 0});
      |                  ~~^~~~~~~~~~
wiring.cpp:13:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |  for (int i = 0; i < B.size(); i++) arr.push_back({B[i], 1});
      |                  ~~^~~~~~~~~~
wiring.cpp:17:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |  for (int i = 1; i < sum.size(); i++) sum[i] = sum[i - 1] + arr[i].first;
      |                  ~~^~~~~~~~~~~~
wiring.cpp:24:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |  for (i++; i < arr.size(); i++) {
      |            ~~^~~~~~~~~~~~
wiring.cpp:39:48: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized]
   39 |    dp[i] = min(dp[i], dp[i-1] + arr[i].first - last);
      |                                                ^~~~
wiring.cpp:34:3: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
   34 |   if (b <= a) {
      |   ^~

• Subtask 1: 7 / 7
• Subtask 2: 13 / 13
• Subtask 3: 10 / 10
• Subtask 4: 25 / 25
• Subtask 5: 45 / 45