单独第一道：  #include<bits/stdc++.h>using namespace std;vector<vector<int> > dir={{0,1},{0,-1},{-1,0},{1,0}};int Fill(vector<vector<int> >& map, int n, int m) {    vector<vector<int> > time(n,vector<int>(m,INT_MAX));    vector<vector<int> > flag(n,vector<int>(m,0));    time[0][0]=0;    queue<vector<int>> q;    vector<int> tmp(2,0);    q.push(tmp);    while(!q.empty()){        vector<int> cur=q.front();        q.pop();        for(int i=0;i<dir.size();++i){            int x=cur[0]+dir[i][0];            int y=cur[1]+dir[i][1];            if(x>=0 && x<n && y>=0 && y<m && map[x][y] ==0 && flag[x][y]==0){                time[x][y]=time[cur[0]][cur[1]]+1;                flag[x][y]=1;                tmp[0]=x;tmp[1]=y;                q.push(tmp);            }        }    }    return time[n-1][m-1];}int main(){    int n;    int m;    int k;    cin>>n>>m>>k;    vector<vector<int>> map(n,vector<int>(m,0));    for(int i=0;i<k;++i){        int row;        int col;        cin>>row>>col;        map[row][col]=1;    }    int res=Fill(map,n,m);    if(res==INT_MAX){        cout<<0<<endl;    }else{        cout<<res<<endl;    }    return 0;}  一起的三道，    其中第一道：      #include<bits/stdc++.h>using namespace std;int main(){    string str;    cin>>str;    string cur;    stack<int> st;    for(int i=0;i<str.size();++i){        if(str[i]=='('){            st.push(i);        }else if(str[i]==')'){            st.pop();        }else{            if(st.empty()){                cur=cur+str[i];            }        }    }    stack<char> chstk;    for(int i=0;i<cur.size();++i){        if(cur[i]=='<'){            if(!chstk.empty()){                chstk.pop();            }        }else{            chstk.push(cur[i]);        }    }    stack<char> res;    while(!chstk.empty()){        res.push(chstk.top());        chstk.pop();    }    while(!res.empty()){        cout<<res.top();        res.pop();    }    cout<<endl;    return 0;} 第二道：  #include<bits/stdc++.h>using namespace std;vector<vector<int> > dir={{0,1},{0,-1},{-1,0},{1,0}};int startx=0;int starty=0;int endx=0;int endy=0;int Fill(vector<string >& map, int n) {    vector<vector<int> > time(n,vector<int>(n,INT_MAX));    vector<vector<int> > flag(n,vector<int>(n,0));    time[startx][starty]=0;    queue<vector<int>> q;    vector<int> tmp={startx,starty};    q.push(tmp);    while(!q.empty()){        vector<int> cur=q.front();        q.pop();        for(int i=0;i<dir.size();++i){            int x=cur[0]+dir[i][0];            int y=cur[1]+dir[i][1];            if(x==-1){                x=n-1;            }else if(x==n){                x=0;            }            if(y==-1){                y=n-1;            }else if(y==n){                y=0;            }            if(x>=0 && x<n && y>=0 && y<n && (map[x][y] =='.' || map[x][y] =='E' )&& flag[x][y]==0){                time[x][y]=time[cur[0]][cur[1]]+1;                if(x==endx && y==endy){                    return time[x][y];                }                flag[x][y]=1;                tmp[0]=x;tmp[1]=y;                q.push(tmp);            }        }    }    return time[endx][endy];}int main(){    int n;    cin>>n;    vector<string> map;    for(int i=0;i<n;++i){        string str;        cin>>str;        for(int j=0;j<str.size();++j){            if(str[j]=='S'){                startx=i;                starty=j;            }            if(str[j]=='E'){                endx=i;                endy=j;            }        }        map.push_back(str);    }    int res=Fill(map,n);    if(res==INT_MAX){        cout<<"-1"<<endl;    }else{        cout<<res<<endl;    }    return 0;}  第三道：    woc，刚被我删掉了。。。没保存。。。    好了，重新打了一下：  #include<bits/stdc++.h>using namespace std;int helper(vector<vector<int> > &vec) {        vector<vector<int>> dp;        sort(vec.begin(),vec.end(),[](vector<int> l,vector<int> r)       {return l[0]<r[0] || (l[0]==r[0] && l[1]<r[1]);});          for(vector<int> cur:vec){                int low=0;                int high=dp.size();                while(low<high){                        int mid=(low+high)/2;                        if(dp[mid][0]<=cur[0] && dp[mid][1]<=cur[1]) {                               low=mid+1;                        }                        else  {                             high=mid;                 }              }            if(high<dp.size())  {                 dp[high]=cur;              }              else dp.push_back(cur);       }        return dp.size();}int main(){        int n;       cin>>n;       vector<vector<int>> vec(n,vector<int>(2,0));      for(int i=0;i<n;++i){              cin>>vec[i][0]>>vec[i][1];      }        cout<<helper(vec)<<endl;        return 0;}