CSU 1333 Funny Car Racing

#include<cstdio>
#include<cmath>
#include<cstring>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;

const int maxn = 305;
vector<int> cost[maxn][maxn];
vector<int> ljb[maxn];
struct abc{ int start, end, aa, bb, cc; }dt[50005];
int flag[maxn], dist[maxn];
int n, m, sx, ex;

void spfa()
{
int i, ii; flag[sx] = 1;
for (i = 0; i <= n; i++) dist[i] = 0x7FFFFFFF;
dist[sx] = 0;
queue<int>Q; Q.push(sx);
while (!Q.empty())
{
int hh = Q.front(); Q.pop(); flag[hh] = 0;
int nowtime = dist[hh];
for (ii = 0; ii < ljb[hh].size(); ii++)
{
for (i = 0; i < cost[hh][ljb[hh][ii]].size(); i++)
{
int id = cost[hh][ljb[hh][ii]][i];
if (dt[id].aa < dt[id].cc) continue;
int yy = nowtime % (dt[id].aa + dt[id].bb);
if (yy <= dt[id].aa)
{
if (yy + dt[id].cc <= dt[id].aa)
{
if (nowtime + dt[id].cc < dist[ljb[hh][ii]])
{
dist[ljb[hh][ii]] = nowtime + dt[id].cc;
if (!flag[ljb[hh][ii]])Q.push(ljb[hh][ii]), flag[ljb[hh][ii]] = 1;
}
}
else
{
if (nowtime + dt[id].aa - yy + dt[id].bb + dt[id].cc < dist[ljb[hh][ii]])
{
dist[ljb[hh][ii]] = nowtime + dt[id].aa - yy + dt[id].bb + dt[id].cc;
if (!flag[ljb[hh][ii]])Q.push(ljb[hh][ii]), flag[ljb[hh][ii]] = 1;
}
}
}
else
{
if (nowtime + dt[id].aa + dt[id].bb - yy + dt[id].cc< dist[ljb[hh][ii]])
{
dist[ljb[hh][ii]] = nowtime + dt[id].aa + dt[id].bb - yy + dt[id].cc;
if (!flag[ljb[hh][ii]])Q.push(ljb[hh][ii]), flag[ljb[hh][ii]] = 1;
}
}
}
}
}
}

int main()
{
int _ = 1;
int i, j, u, v, a, b, c;
while (~scanf("%d%d%d%d", &n, &m, &sx, &ex))
{
for (i = 0; i <= n; i++) ljb[i].clear();
for (i = 0; i <= n; i++) for (j = 0; j <= n; j++) cost[i][j].clear();
memset(flag, 0, sizeof(flag));
for (i = 0; i < m; i++)
{
scanf("%d%d%d%d%d", &u, &v, &a, &b, &c);
dt[i].start = u; dt[i].end = v;
dt[i].cc = c; dt[i].aa = a; dt[i].bb = b;
cost[u][v].push_back(i);
ljb[u].push_back(v);
}
spfa();
printf("Case %d: %d\n", _++, dist[ex]);
}
return 0;
}