# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
927695 | LonlyR | Robot (JOI21_ho_t4) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
#define int long long
#define ii pair<int,int>
#define ff first
#define ss second
using namespace std;
const int maxn = 2e5 + 5;
int n, m;
int dp[maxn];
vector<array<int, 3>> adj[maxn];
map<int,int> col[maxn];
map<int,int> dpc[maxn];
map<int,vector<ii>> adjc[maxn];
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
// freopen("test.inp", "r", stdin);
// freopen("test.out", "w", stdout);
cin >> n >> m;
for (int i = 1, u, v, w, t; i <= m; i++)
{
cin >> u >> v >> w >> t;
adj[u].push_back({v, w, t});
adj[v].push_back({u, w, t});
adjc[u][w].emplace_back(v, t);
adjc[v][w].emplace_back(u, t);
col[u][w] += t;
col[v][w] += t;
}
#define iii tuple<int,int,int>
priority_queue<iii, vector<iii>, greater<iii>> pq;
memset(dp, 0x3f, sizeof dp);
int oo = dp[0];
dp[1] = 0;
pq.emplace(0, 1, 0);
while (pq.size())
{
int u, v, w;
tie(v, u, w) = pq.top();
pq.pop();
if (w == 0)
{
if (v != dp[u]) continue;
for (auto p : adj[u])
{
int color = p[1], cost = p[2], nxt = p[0];
int val = v + cost, f = 0;
if (dp[nxt] > val)
dp[nxt] = val,
f = 1;
if (!dpc[nxt].count(color) || dpc[nxt][color] > val - cost)
dpc[nxt][color] = val - cost,
pq.emplace(val - cost, nxt, color);
val = v + col[u][color] - cost;
if (dp[nxt] > val)
dp[nxt] = val,
f = 1;
if (f) pq.emplace(dp[nxt], nxt, 0);
}
}
else
{
if (v != dpc[u][w]) continue;
for (auto p : adjc[u][w])
{
int nxt = p.ff, cost = p.ss, color = w;
val = v + col[u][color] - cost;
if (dp[nxt] > val)
dp[nxt] = val,
f = 1;
if (f) pq.emplace(dp[nxt], nxt, 0);
}
}
}
cout << (dp[n] == oo ? -1 : dp[n]);
}