天池在线编程限时赛 --- 【夕阳下的奔跑场】脱单队

class Solution {
public:
    /**
     * @param str: The first string given
     * @param sub: The given second string
     * @return: Returns the deleted string
     */
    string CharacterDeletion(string &str, string &sub) {
        // write your code here
    char buf[256] = { 0 };
	for (int i = 0; i < sub.size(); i++)
	{
		buf[sub[i]]++;
	}
	string ret;
	for (int i = 0; i < str.size(); i++)
	{
		if (buf[str[i]] == 0)
			ret += str[i];
	}
	return ret;

    }
};

class Solution {
public:
    /**
     * @param Mine_map: an array represents the map.
     * @param Start: the start position.
     * @return: return an array including all reachable positions.
     */
     using pii = pair<int,int>;
    vector<vector<int>> Mine_sweeping(vector<vector<int>> &Mine_map, vector<int> &Start) {
        // write your code here
        	int dx[] = {-1,1,0,0};
			int dy[] = {0,0,-1,1};
			queue<pii> q;
			q.emplace(Start[0],Start[1]);
			int n=Mine_map.size(),m=Mine_map[0].size();
			auto check = [&](int x,int y){
				return x >= 0 && x < n && y>=0 && y<m; 
			};
			set<vector<int>> temp;
			while(q.size()){
				auto t = q.front();
				q.pop();
				int i=t.first,j=t.second;
				temp.insert(vector<int>{i,j});
				if(!Mine_map[i][j]) continue;
				Mine_map[i][j] = 0;
				for(int k=0;k<4;k++){
					int x = i + dx[k];
					int y = j + dy[k];
					if(check(x,y)) q.emplace(x,y);
				}
			}
			return vector<vector<int>>(temp.begin(),temp.end()); 
    }
};

class Solution {
public:
    /**
     * @param arr: the distance between any two cities
     * @return: the minimum distance Alice needs to walk to complete the travel plan
     */
    int travelPlan(vector<vector<int>> &arr) {
        // Write your code here.
        int n = arr.size();
        vector<int> a;
        for(int i=1;i<n;i++) a.emplace_back(i);
        int ans  =INT_MAX;
        do{
          int mini = 0,now = 0;
          for(auto nxt : a){
          mini += arr[now][nxt];
          now = nxt;
          }
          ans = min(ans,mini + arr[now][0]);
        }while(next_permutation(a.begin(),a.end()));
        return ans;
    }
};