Codeforces Beta Round #95 (Div. 2)

简单总结一下昨晚的cf。两个字：脑残

手速太慢（maybe天气冷到手有点僵），水题都不会水了，组合数那题竟然开eclipse去做！脑残到不会用数组递推，D题图论题意大概看懂就开始搞，搞到很慢，临结束还有2min才交，不过幸运的是1A，E也是水题，不够时间搞。哎，注定只能做div2了=。=

ABC水不贴代码。

D图论，把一个图中成环的点输出0，其他点就输出到环的距离就ok，我的做法是开始先类似拓扑排序那样，依次删去度为1的点，剩下的就是环中的点，再bfs求其余点离环的距离，代码写得有点搓。

#include <map>#include <set>#include <list>#include <queue>#include <deque>#include <stack>#include <string>#include <time.h>#include <cstdio>#include <math.h>#include <iomanip>#include <cstdlib>#include <limits.h>#include <string.h>#include <iostream>#include <fstream>#include <algorithm>using namespace std;#define LL long long#define MIN INT_MIN#define MAX INT_MAX#define PI acos(-1.0)#define FRE freopen("input.txt","r",stdin)#define FF freopen("output.txt","w",stdout)#define N 3005vector<int> v[N];int n;queue<int> qq;int du[N];struct node{    int id;    int t;};queue<node> q;int ans[N];bool vis[N];int main(){    cin>>n;    int i,j;    memset(vis,0,sizeof(vis));    for (i=0;i<n;i++) {        int x,y;        cin>>x>>y;        v[x].push_back(y);        v[y].push_back(x);        du[x]++;        du[y]++;    }    for (i=1;i<=n;i++) {        if (du[i] == 1) {            qq.push(i);        }    }    while(!qq.empty()){        int x = qq.front();        qq.pop();        du[x]--;        for (i = 0 ;i < v[x].size(); i++) {            int y = v[x][i];            du[y]--;            if (du[y] == 1 ){                qq.push(y);            }        }    }    while(!qq.empty())qq.pop();    for (i=1;i<=n;i++){        if (du[i]==2){            ans[i] = 0;            node tmp;            tmp.t = i;            tmp.id = 0;            q.push(tmp);vis[i] = 1;        }    }    while(!q.empty()){//cout<<"!"<<endl;        node x = q.front();        q.pop();        vis[x.t] = 1;        for (i=0;i<v[x.t].size();i++){            int y = v[x.t][i];            if (vis[y])continue;            vis[y]=1;            ans[y] = x.id+1;            node tmp;            tmp.t = y;            tmp.id = x.id+1;            q.push(tmp);        }    }    for(i=1;i<=n;i++)cout<<ans[i]<<" ";    cout<<endl;    return 0;}

E模拟，4次排序：正对角、副对角、x方向、y方向排序，注意处理好细节，要保证排好后同一直线上相邻两个点之间必须没有点，否则会wa

#include <map>#include <set>#include <list>#include <queue>#include <deque>#include <stack>#include <string>#include <time.h>#include <cstdio>#include <math.h>#include <iomanip>#include <cstdlib>#include <limits.h>#include <string.h>#include <iostream>#include <fstream>#include <algorithm>using namespace std;#define LL long long#define MIN INT_MIN#define MAX INT_MAX#define PI acos(-1.0)#define FRE freopen("input.txt","r",stdin)#define FF freopen("output.txt","w",stdout)#define N 100005struct node{    int x,y;    int id;}p[N],q[N];int num[N];int ans[10];bool cmp1(node a,node b){    if  (a.x+a.y==b.x+b.y)return (a.x < b.x && a.y > b.y);    return a.x+a.y<b.x+b.y;}bool cmp2(node a, node b) {    if (a.y - a.x != b.y - b.x) {        return a.y - a.x < b.y - b.x;    } else {        return a.x < b.x;    }}bool cmp3(node a,node b){    if (a.x == b.x) return a.y < b.y;    return a.x < b.x;}bool cmp4(node a,node b){    if (a.y == b.y) return a.x < b.x;    return a.y < b.y;}///////////////////////////////int main(){    int n,m;    cin>>n>>m;    int i;    for (i=0;i<m;i++) {        cin>>p[i].x>>p[i].y;        p[i].id = i;    }    for (i=0;i<m;i++) {        q[i].x = p[i].x;        q[i].y = p[i].y;        q[i].id = p[i].id;    }    sort(q,q+m,cmp1);    for (i = 0; i+1 < m; i++){        if ((q[i].x+q[i].y) == (q[i+1].x + q[i+1].y)) {            num[q[i].id]++;            num[q[i+1].id]++;        }    }    //for (i=0;i<m;i++)cout<<q[i].x<<" "<<q[i].y<<endl;   // cout<<num[i]<<endl;////////////////////////////////////////    for (i=0;i<m;i++) {        q[i].x = p[i].x;        q[i].y = p[i].y;        q[i].id = p[i].id;    }    sort(q,q+m,cmp2);    for (i = 0; i+1 < m; i++){        if ((q[i].x-q[i+1].x) == (q[i].y - q[i+1].y)) {            num[q[i].id]++;num[q[i+1].id]++;        }    }////////////////////////////////////////////    for (i=0;i<m;i++) {        q[i].x = p[i].x;        q[i].y = p[i].y;        q[i].id = p[i].id;    }    sort(q,q+m,cmp3);    for (i = 0; i+1 < m; i++){        if (q[i].x == q[i+1].x) {            num[q[i].id]++;num[q[i+1].id]++;        }    }/////////////////////////////////////////////////    for (i=0;i<m;i++) {        q[i].x = p[i].x;        q[i].y = p[i].y;        q[i].id = p[i].id;    }    sort(q,q+m,cmp4);    for (i = 0; i+1 < m; i++){        if (q[i].y == q[i+1].y) {            num[q[i].id]++;num[q[i+1].id]++;        }    }/////////////////////////////////////////////////    for (i = 0 ; i < m; i++) {        ans[num[i]]++;    }    for (i = 0 ; i  < 9;i++) {        cout<<ans[i]<<" ";    }cout<<endl;    return 0;}