#include <cstdio>
#include <algorithm>
#include <iostream>
#define maxn (10000 + 10)
using namespace std;

const int inf = 1000000000;
int n, d[maxn], ans, m, e;
pair<pair<int, int>, int>p[maxn];

void init(){
	for(int i = 0; i < n; i++) d[i] = inf; ans = inf;
}

int main(){
	scanf("%d %d %d", &n, &m, &e);
	init();
	for(int i = 0; i < n; i++){
		scanf("%d %d %d", &p[i].first.first, &p[i].first.second, &p[i].second);
	}
	sort(p, p + n);
	for(int i = 0; i < n; i++) if(p[i].first.first == m) d[i] = 0;
	for(int i = 0; i < n; i++){
		int c = p[i].second, t = d[i], pl = p[i].first.second + 1;
		for(int j = i + 1; j < n && p[j].first.first <= pl; j++){
			d[j] = min(d[j], t + c);
		}
	}
	for(int i = 0; i < n; i++){
		if(p[i].first.second == e){
			ans = min(ans, d[i] + p[i].second);
		}
	}
	printf("%d\n", (ans != inf ? ans : -1));
	return 0;
}

• Re:WHY FEW ACCEPTED FOR SUCH A EASY PROBLEM (49) JustForU 2011-08-02 09:26:06
  • Re:WHY FEW ACCEPTED FOR SUCH A EASY PROBLEM (22) hassenio 2011-08-15 20:25:21