<p>A robot on an infinite XY-plane starts at point <code>(0, 0)</code> facing north. The robot receives an array of integers <code>commands</code>, which represents a sequence of moves that it needs to execute. There are only three possible types of instructions the robot can receive:</p>

<ul>
	<li><code>-2</code>: Turn left <code>90</code> degrees.</li>
	<li><code>-1</code>: Turn right <code>90</code> degrees.</li>
	<li><code>1 &lt;= k &lt;= 9</code>: Move forward <code>k</code> units, one unit at a time.</li>
</ul>

<p>Some of the grid squares are <code>obstacles</code>. The <code>i<sup>th</sup></code> obstacle is at grid point <code>obstacles[i] = (x<sub>i</sub>, y<sub>i</sub>)</code>. If the robot runs into an obstacle, it will stay in its current location (on the block adjacent to the obstacle) and move onto the next command.</p>

<p>Return the <strong>maximum squared Euclidean distance</strong> that the robot reaches at any point in its path (i.e. if the distance is <code>5</code>, return <code>25</code>).</p>

<p><strong>Note:</strong></p>

<ul>
	<li>There can be an obstacle at <code>(0, 0)</code>. If this happens, the robot will ignore the obstacle until it has moved off the origin. However, it will be unable to return to <code>(0, 0)</code> due to the obstacle.</li>
	<li>North means +Y direction.</li>
	<li>East means +X direction.</li>
	<li>South means -Y direction.</li>
	<li>West means -X direction.</li>
</ul>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">commands = [4,-1,3], obstacles = []</span></p>

<p><strong>Output:</strong> <span class="example-io">25</span></p>

<p><strong>Explanation: </strong></p>

<p>The robot starts at <code>(0, 0)</code>:</p>

<ol>
	<li>Move north 4 units to <code>(0, 4)</code>.</li>
	<li>Turn right.</li>
	<li>Move east 3 units to <code>(3, 4)</code>.</li>
</ol>

<p>The furthest point the robot ever gets from the origin is <code>(3, 4)</code>, which squared is <code>3<sup>2</sup> + 4<sup>2 </sup>= 25</code> units away.</p>
</div>

<p><strong class="example">Example 2:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">commands = [4,-1,4,-2,4], obstacles = [[2,4]]</span></p>

<p><strong>Output:</strong> <span class="example-io">65</span></p>

<p><strong>Explanation:</strong></p>

<p>The robot starts at <code>(0, 0)</code>:</p>

<ol>
	<li>Move north 4 units to <code>(0, 4)</code>.</li>
	<li>Turn right.</li>
	<li>Move east 1 unit and get blocked by the obstacle at <code>(2, 4)</code>, robot is at <code>(1, 4)</code>.</li>
	<li>Turn left.</li>
	<li>Move north 4 units to <code>(1, 8)</code>.</li>
</ol>

<p>The furthest point the robot ever gets from the origin is <code>(1, 8)</code>, which squared is <code>1<sup>2</sup> + 8<sup>2</sup> = 65</code> units away.</p>
</div>

<p><strong class="example">Example 3:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">commands = [6,-1,-1,6], obstacles = [[0,0]]</span></p>

<p><strong>Output:</strong> <span class="example-io">36</span></p>

<p><strong>Explanation:</strong></p>

<p>The robot starts at <code>(0, 0)</code>:</p>

<ol>
	<li>Move north 6 units to <code>(0, 6)</code>.</li>
	<li>Turn right.</li>
	<li>Turn right.</li>
	<li>Move south 5 units and get blocked by the obstacle at <code>(0,0)</code>, robot is at <code>(0, 1)</code>.</li>
</ol>

<p>The furthest point the robot ever gets from the origin is <code>(0, 6)</code>, which squared is <code>6<sup>2</sup> = 36</code> units away.</p>
</div>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= commands.length &lt;= 10<sup>4</sup></code></li>
	<li><code>commands[i]</code> is either <code>-2</code>, <code>-1</code>, or an integer in the range <code>[1, 9]</code>.</li>
	<li><code>0 &lt;= obstacles.length &lt;= 10<sup>4</sup></code></li>
	<li><code>-3 * 10<sup>4</sup> &lt;= x<sub>i</sub>, y<sub>i</sub> &lt;= 3 * 10<sup>4</sup></code></li>
	<li>The answer is guaranteed to be less than <code>2<sup>31</sup></code>.</li>
</ul>

int speedUp = [] {
    std::ios::sync_with_stdio(0);
    std::cin.tie(0);
    return 0;
}();
class Solution {
public:
    int robotSim(vector<int>& cmd, vector<vector<int>>& obstacles) {
        int n = cmd.size();
        int m = obstacles.size();
        unordered_map<string, int> ob;
        for(auto it: obstacles){
            string key = to_string(it[0]) + ',' + to_string(it[1]);
            ob[key]++;
        }
        int ans = 0;
        bool vert = true;
        int x=0, y=0;
        int i = 0;
        vector<vector<int>> rot = {{0,1},{1,0},{0,-1},{-1,0}};
        for(auto it: cmd){
            if(it>0){
                bool collide = false;
                for(int j = 1; j<=it; j++){
                    int nx = x + rot[i][0];
                    int ny = y + rot[i][1];
                    string key = to_string(nx) + ',' + to_string(ny);
                    if(ob.find(key)!=ob.end()) {
                        bool collide = true;
                        break;
                    }
                    if(collide) continue;
                    x = nx; y = ny;
                }
                ans = max(ans, x*x + y*y);
            }
            else{
                if(it == -1){
                    i++;
                    if(i==4) i = 0;
                }
                else{
                    i--;
                    if(i==-1) i = 3;
                }
            }
        }
        // for (int i = 0; i < n; i++) {
        //     if (cmd[i] > 0) {
        //         int dirn = rot[j];
        //         int steps = cmd[i];
        //         if(vert){
        //             if(dirn>0){
        //                 while(steps){
        //                     y++;
        //                     if(collision(ob, x, y)) {y--; break;}
        //                     steps--;
        //                 }
        //             }
        //             else{
        //                 while(steps){
        //                     y--;
        //                     if(collision(ob, x, y)) {y++; break;}
        //                     steps--;
        //                 }
        //             }
        //         }
        //         else {
        //             if(dirn>0){
        //                 while(steps){
        //                     x++;
        //                     if(collision(ob,x,y)) {x--; break;}
        //                     steps--;
        //                 }
        //             }
        //             else{
        //                 while(steps){
        //                     x--;
        //                     if(collision(ob,x,y)) {x++; break;}
        //                     steps--;
        //                 }
        //             }
        //         }
        //         ans = max(ans, dist(x,y));
        //     }
        //     else{
        //         vert = !vert;
        //         if(cmd[i]==-1){
        //             j++;
        //             if(j==4) j = 0;
        //         }
        //         else {
        //             j--;
        //             if (j==-1) j=3;
        //         }
        //     }
        // }
        return ans;
    }
};
44213