int openLock(vector<string> &deadends, string &target) {
// Write your code here
unordered_set<string> visited, deads;
for(auto deadend: deadends)
deads.insert(deadend);
if(deads.find("0000") != deads.end())
return -1;
queue<pair<string, int>> combs;
combs.push({"0000", 0});
visited.insert("0000");
string next;
pair<string, int> current;
while(!combs.empty())
{
current = combs.front();
combs.pop();
if(current.first == target)
break;
for(int i = 0; i < 4; i++)
{
next = rotate(current.first, i, true);
push_next(visited, deads, combs, next, current.second + 1);
next = rotate(current.first, i, false);
push_next(visited, deads, combs, next, current.second + 1);
}
}
if(current.first == target)
return current.second;
return -1;
}
void Fl_Help_Dialog::previous_url()
{
char *url = pop_prev();
if(url) {
no_prevpush = true;
push_next(htmlWidget->filename());
htmlWidget->load(url);
label(htmlWidget->title());
delete []url;
no_prevpush = false;
}
}
inline void
NavFn::updateCellAstar(int n)
{
// get neighbors
float u,d,l,r;
l = potarr[n-1];
r = potarr[n+1];
u = potarr[n-nx];
d = potarr[n+nx];
//ROS_INFO("[Update] c: %0.1f l: %0.1f r: %0.1f u: %0.1f d: %0.1f\n",
// potarr[n], l, r, u, d);
// ROS_INFO("[Update] cost of %d: %d\n", n, costarr[n]);
// find lowest, and its lowest neighbor
float ta, tc;
if (l<r) tc=l; else tc=r;
if (u<d) ta=u; else ta=d;
// do planar wave update
if (costarr[n] < COST_OBS) // don't propagate into obstacles
{
float hf = (float)costarr[n]; // traversability factor
float dc = tc-ta; // relative cost between ta,tc
if (dc < 0) // ta is lowest
{
dc = -dc;
ta = tc;
}
// calculate new potential
float pot;
if (dc >= hf) // if too large, use ta-only update
pot = ta+hf;
else // two-neighbor interpolation update
{
// use quadratic approximation
// might speed this up through table lookup, but still have to
// do the divide
float d = dc/hf;
float v = -0.2301*d*d + 0.5307*d + 0.7040;
pot = ta + hf*v;
}
//ROS_INFO("[Update] new pot: %d\n", costarr[n]);
// now add affected neighbors to priority blocks
if (pot < potarr[n])
{
float le = INVSQRT2*(float)costarr[n-1];
float re = INVSQRT2*(float)costarr[n+1];
float ue = INVSQRT2*(float)costarr[n-nx];
float de = INVSQRT2*(float)costarr[n+nx];
// calculate distance
int x = n%nx;
int y = n/nx;
float dist = (x-start[0])*(x-start[0]) + (y-start[1])*(y-start[1]);
dist = sqrtf(dist)*(float)COST_NEUTRAL;
potarr[n] = pot;
pot += dist;
if (pot < curT) // low-cost buffer block
{
if (l > pot+le) push_next(n-1);
if (r > pot+re) push_next(n+1);
if (u > pot+ue) push_next(n-nx);
if (d > pot+de) push_next(n+nx);
}
else
{
if (l > pot+le) push_over(n-1);
if (r > pot+re) push_over(n+1);
if (u > pot+ue) push_over(n-nx);
if (d > pot+de) push_over(n+nx);
}
}
}
}
