1018. Public Bike Management (30)

#include<iostream>
#include<vector>
#define INF 0x3f3f3f
#define MAX_bike 102
#define MAX_V 502
using namespace std;
int C, N, sp, M;
int t_min=INF;int send=0, back=0;vector<int> path;//输出变量
int temp_send=0, temp_back=0,temp_min=0;vector<int> temp_path;//临时变量
int arc[MAX_V][MAX_V] = {0};//邻接矩阵
int bike[MAX_V];//顶点自行车数量
bool visited[MAX_V];//bfs中是否被访问
void intipath()//对路径求temp_back和temp_send
{
int temp;
temp = 0, temp_send = 0;
for (auto x : temp_path)
{
if (bike[x] + temp < 0)
{
temp_send += -(bike[x] + temp);temp = 0;
}
else temp = bike[x] + temp;
}
temp_back = temp;
}
void bfs(int index)//bfs
{
if (temp_min > t_min) { return; }//剪枝
if (index == sp)
{
intipath();
if (temp_min < t_min || (temp_min==t_min && temp_send<send)||(temp_min==t_min && temp_send==send && temp_back<back) )
{
t_min = temp_min;send = temp_send;back = temp_back;path = temp_path;
}
return;
}
for (int t = 1;t <= N;t++)
{
if (visited[t] == false && arc[index][t] != 0)
{
visited[t] = true;
temp_path.push_back(t);
temp_min += arc[index][t];
bfs(t);
visited[t] = false;//回溯
temp_path.pop_back();
temp_min -= arc[index][t];
}
}
}

int main()
{
cin >> C >> N >> sp >> M;
bike[0] = 0;
for (int t = 1;t <= N;t++)
{
cin >> bike[t];
bike[t] -= C / 2;
}
for (int t = 0;t < M;t++)
{
int i, j,k;
cin >> i >> j >> k;
arc[i][j] = arc[j][i]=k;
}
visited[0] = true;
bfs(0);
cout << send << " 0";

for (auto it = path.begin();it != path.end();it++)
cout << "->" << *it;
cout << " " << back << endl;

return 0;

}

#include<iostream>
#include<vector>
#define MAX_V 502
#define MAX_bike 102
#define INF 0x3f3f3f

//vector保存的路径不包括0
using namespace std;
vector<vector<int>> temp_path[MAX_V];//临时路径，求所有最短路径解
int arc[MAX_V][MAX_V] = {0};//邻接矩阵
int bike[MAX_V];//顶点自行车数量
int D[MAX_V] = {0};//最短路径
int temp_D[MAX_V];//DIJ临时变量
int C, N, sp, M;
int temp_send, temp_back;
vector<int> path;int send=INF, back;//最后要输出的
void DIJ()
{
for (int t = 1;t <= N;t++)
if (arc[0][t] != 0) temp_D[t] = arc[0][t];

while (D[sp] == 0)
{

int temp_min=INF, temp_v;
for (int t = 1;t <= N;t++)
if (D[t]==0 && temp_D[t] < temp_min)
{
temp_min = temp_D[t];
temp_v = t;
}
D[temp_v] = temp_min;
for (auto &x : temp_path[temp_v])
x.push_back(temp_v);
for (int t = 1;t <= N;t++)//更新temp_D
{
if (D[t] == 0 && arc[temp_v][t]!=0)
{
if (temp_min + arc[temp_v][t] < temp_D[t])
{
temp_D[t] = temp_min + arc[temp_v][t];
temp_path[t] = temp_path[temp_v];
}
else if (temp_min + arc[temp_v][t] == temp_D[t])
{
temp_path[t].insert(temp_path[t].end(), temp_path[temp_v].begin(), temp_path[temp_v].end());
}
}
}

}

}

void intipath(vector<int> p)
{
temp_send = 0;
int temp = 0;
for (auto x : p)
{
if (temp + bike[x] < 0)
{
temp_send += -(temp + bike[x]);
temp = 0;
}
else
temp = temp + bike[x];
}
temp_back = temp;
}

int main()
{
cin >> C >> N >> sp >> M;
vector<int> vec;
for (int t = 1;t <= N;t++)
{
cin >> bike[t];
bike[t] -= C / 2;
temp_D[t] = INF;//初始化
temp_path[t].push_back(vec);
}
for (int t = 0;t < M;t++)
{
int i, j,k;
cin >> i >> j >> k;
arc[i][j] = arc[j][i] = k;
}
DIJ();
for (auto x : temp_path[sp])
{
intipath(x);
if (temp_send < send || (temp_send == send && temp_back < back))
{
path = x;
send = temp_send;
back = temp_back;
}

}
cout << send << " 0";
for (auto x : path)
cout << "->" << x;
cout << " " << back << endl;
}