POJ 1062 昂贵的聘礼

/*
*POJ 1062 昂贵的聘礼
*代码参考: http://poj.org/showmessage?message_id=344843
*/

#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

const int MAXN = 110;
const int INF = 0x3f3f3f3f;
int dist[MAXN], edge[MAXN][MAXN], level[MAXN];
bool visit[MAXN];
int n, m;
int dijkstra()
{
	int i, j;
	for (i = 0; i <= n; i++) {
		dist[i] = edge[0][i];
	}
	visit[0] = 1;
	for (i = 1; i < n; i++) {
		int min = INF;
		int u = 0;
		for (j = 1; j <= n; j++) {
			if (!visit[j] && dist[j] < min) {
				u = j;
				min = dist[j];
			}
		}
		visit[u] = 1;
		for (j = 1; j <= n; j++) {
			if (!visit[j] && edge[u][j] < INF && dist[u] + edge[u][j] < dist[j]) {
				dist[j] = dist[u] + edge[u][j];
			}
		}
	}
	return dist[1];
}

int main()
{
	int i, j, num, temp;
	while (~scanf("%d %d", &m, &n)) {
		for (i = 0; i <= n; i++) {
			for (j = 0; j <= n; j++) {
				edge[i][j] = INF;
			}
			edge[i][i] = 0;
		}
		memset(level, 0, sizeof(level));
		memset(visit, 0, sizeof(visit));
		for (i = 1; i <= n; i++) {
			scanf("%d %d %d", &edge[0][i], &level[i], &num);
			for (j = 1; j <= num; j++) {
				scanf("%d", &temp);
				scanf("%d", &edge[temp][i]);
			}
		}
		int ans = INF;
		for (i = 1; i <= n; i++) {
			int lv = level[i];
			for (j = 1; j <= n; j++) {
				if (level[j] > lv || lv - level[j] > m) {
					visit[j] = 1;
				} else {
					visit[j] = 0;
				}
			}
			int min = dijksttra();
			if (ans > min) {
				ans = min;
			}
		}
		printf("%d\n", ans);
	}
	return 0;
}