[ZJOI2006]物流运输

题目地址：

https://ac.nowcoder.com/acm/problem/20469

基本思路:

参考代码：

#pragma GCC optimize(2)
#pragma GCC optimize(3)
#include <bits/stdc++.h>
using namespace std;
#define IO std::ios::sync_with_stdio(false); cin.tie(0)
#define int long long
#define ull unsigned long long
#define SZ(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rep(i, l, r) for (int i = l; i <= r; i++)
#define per(i, l, r) for (int i = l; i >= r; i--)
#define mset(s, _) memset(s, _, sizeof(s))
#define pb push_back
#define pii pair <int, int>
#define mp(a, b) make_pair(a, b)
#define INF 0x3f3f3f3f

inline int read() {
  int x = 0, neg = 1; char op = getchar();
  while (!isdigit(op)) { if (op == '-') neg = -1; op = getchar(); }
  while (isdigit(op)) { x = 10 * x + op - '0'; op = getchar(); }
  return neg * x;
}
inline void print(int x) {
  if (x < 0) { putchar('-'); x = -x; }
  if (x >= 10) print(x / 10);
  putchar(x % 10 + '0');
}

int n,m,K,e,d;
bool can[25][110],bk[25];

int mm[25][25],dis[25][25];
int floyd(int a,int b) {
  mset(bk, false);
  rep(i, 1, m) rep(j, a, b) if (!can[i][j]) bk[i] = true;
  rep(i, 1, m) rep(j, 1, m) if (!bk[i] && !bk[j]) dis[i][j] = mm[i][j]; else dis[i][j] = INF;
  rep(k, 1, m) rep(i, 1, m) rep(j, 1, m) dis[i][j] = min(dis[i][j], dis[i][k] + dis[k][j]);
  return dis[1][m];
}

int l[110][110],dp[110];
signed main() {
  IO;
  cin >> n >> m >> K >> e;
  for(int i = 1 ; i <= m ; i++){
    for(int j = 1 ; j <= m ; j++) mm[i][j] = INF;
    mm[i][i] = 0;
  }
  rep(i,1,e) {
    int u, v, w;
    cin >> u >> v >> w;
    mm[u][v] = min(mm[u][v],w);
    mm[v][u] = min(mm[v][u],w);
  }
  cin >> d;
  mset(can,true);
  rep(i,1,d) {
    int p, a, b;
    cin >> p >> a >> b;
    for (int j = a; j <= b; j++) can[p][j] = false;
  }
  for(int i = 1 ; i <= n ; i++) {
    for(int j = i ; j <= n ; j++) l[i][j] = floyd(i,j);
  }
  for(int i = 1 ; i <= n ; i++){
    dp[i] = l[1][i] * i;
    for(int j = 0 ; j < i ; j++) dp[i] = min(dp[i],dp[j] + K + l[j + 1][i] * (i - j));
  }
  cout << dp[n] << '\n';
  return 0;
}