HDU-2722-Here We Go(relians) Again

描述

题解

代码

#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
#include <utility>

using namespace std;

typedef pair<int, int> pii;
const int INF = 0x3f3f3f3f;
const int MAXN = 100;
const int MAXV = 445;
const int MAXE = MAXV * MAXV / 2;
const int MAXL = 2520;

struct Edge
{
int v, next, w;
} E[MAXE];

int n;
int m;
int vn;
int size;
int head[MAXV];
int lowcost[MAXV];

void addEdge(int u, int v, int w)
{
E[size].v = v;
E[size].w = w;
E[size].next = head[u];
head[u] = size++;
}

void init()
{
vn = (m + 1) * (n + 1);
size = 0;
memset(head, -1, sizeof(head));
}

void Dijkstra(int src)
{
memset(lowcost, 0x3f, sizeof(lowcost));

lowcost[src] = 0;
priority_queue<pii, vector<pii>, greater<pii> > q;
q.push(make_pair(lowcost[src],src));

while (!q.empty())
{
pii x = q.top();
q.pop();
int u = x.second;
if (lowcost[u] != x.first)
{
continue;
}
for (int e = head[u]; e != -1; e = E[e].next)
{
int tmp = lowcost[u] + E[e].w;
if (lowcost[E[e].v] > tmp)
{
lowcost[E[e].v] = tmp;
q.push(make_pair(tmp, E[e].v));
}
}
}
}

int main()
{
char str[MAXN];

int u, w;
while (~scanf("%d%d%*c", &n, &m) && n + m)
{
init();

for (int i = 1; i <= n * 2 + 1; ++i)
{
fgets(str, MAXN, stdin);
int len = (int)strlen(str);
if (i & 1)
{
for (int j = 0, k = 1; j < len; j += 4, ++k)
{
u = (m + 1) * (i / 2) + k;
w = str[j] - '0';
if (w == 0)
{
continue;
}
if (str[j + 2] == '*')
{
addEdge(u, u + 1, MAXL / w);
addEdge(u + 1, u, MAXL / w);
}
else if (str[j + 2] == '<')
{
addEdge(u + 1, u, MAXL / w);
}
else
{
addEdge(u, u + 1, MAXL / w);
}
}
}
else
{
for (int j = 0, k = 1; j < len; j += 4, ++k)
{
u = (m + 1) * (i / 2 - 1) + k;
w = str[j] - '0';
if (w == 0)
{
continue;
}
if (str[j + 2] == '*')
{
addEdge(u, u + m + 1, MAXL / w);
addEdge(u + m + 1, u, MAXL / w);
}
else if (str[j + 2] == 'v')
{
addEdge(u, u + m + 1, MAXL / w);
}
else if (str[j + 2] == '^')
{
addEdge(u + m + 1, u, MAXL / w);
}
}
}
}

Dijkstra(1);

if (lowcost[vn] != INF)
{
printf("%d blips\n", lowcost[vn]);
}
else
{
puts("Holiday");
}
}

return 0;
}

参考