Codeforces Round #363 (Div. 2)

最近太忙了时间不够, 4个1a 记录一下代码 剩4题有空补做吧

http://codeforces.com/contest/699

A

//#define txtout
//#define debug
#include<bits/stdc++.h>
#define mt(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;
const double pi=acos(-1.0);
const double eps=1e-8;
const int inf=0x3f3f3f3f;
const int M=2e5+10;
int n;
char a[M];
int b[M];
int solve(){
    int answer=inf;
    for(int i=0;i<n;i++){
        if(a[i]=='L') continue;
        int last=i;
        for(int j=i;j<n;j++){
            if(a[j]=='L') break;
            last=j;
        }
        if(last==n-1) break;
        answer=min(answer,(b[last+1]-b[last])/2);
        i=last;
    }
    if(answer==inf) answer=-1;
    return answer;
}
int main(){
    #ifdef txtout
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
    #endif // txtout
    while(~scanf("%d%s",&n,a)){
        for(int i=0;i<n;i++){
            scanf("%d",&b[i]);
        }
        printf("%d
",solve());
    }
    return 0;
}

B

//#define txtout
//#define debug
#include<bits/stdc++.h>
#define mt(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;
const double pi=acos(-1.0);
const double eps=1e-8;
const int inf=0x3f3f3f3f;
const int M=1e3+10;
int n,m;
char a[M][M];
int sum;
int row[M];
int clum[M];
void init(){
    mt(row,0);
    mt(clum,0);
    sum=0;
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            if(a[i][j]=='.') continue;
            sum++;
            row[i]++;
            clum[j]++;
        }
    }
}
void solve(){
    init();
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            int temp=sum-row[i]-clum[j];
            if(a[i][j]=='*') temp++;
            if(temp==0){
                puts("YES");
                printf("%d %d
",i+1,j+1);
                return ;
            }
        }
    }
    puts("NO");
}
int main(){
    #ifdef txtout
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
    #endif // txtout
    while(~scanf("%d%d",&n,&m)){
        for(int i=0;i<n;i++){
            scanf("%s",a[i]);
        }
        solve();
    }
    return 0;
}

C

//#define txtout
//#define debug
#include<bits/stdc++.h>
#define mt(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;
const double pi=acos(-1.0);
const double eps=1e-8;
const int inf=0x3f3f3f3f;
const int M=1e2+10;
int n;
int a[M];
int dp[M][4];
int solve(){
    for(int i=0;i<n;i++){
        for(int j=0;j<3;j++){
            dp[i][j]=inf;
        }
    }
    dp[0][2]=1;
    for(int i=0;i<2;i++){
        if((a[0]>>i)&1){
            dp[0][i]=0;
        }
    }
    for(int i=0;i<n-1;i++){
        for(int j=0;j<3;j++){
            dp[i+1][2]=min(dp[i+1][2],dp[i][j]+1);
            for(int k=0;k<2;k++){
                if((a[i+1]>>k)&1){
                    dp[i+1][k]=min(dp[i+1][k],dp[i][2]);
                    dp[i+1][k]=min(dp[i+1][k],dp[i][k^1]);
                }
            }
        }
    }
    int result=inf;
    for(int j=0;j<3;j++){
        result=min(result,dp[n-1][j]);
    }
    return result;
}
int main(){
    #ifdef txtout
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
    #endif // txtout
    while(~scanf("%d",&n)){
        for(int i=0;i<n;i++){
            scanf("%d",&a[i]);
        }
        printf("%d
",solve());
    }
    return 0;
}

D

//#define txtout
//#define debug
#include<bits/stdc++.h>
#define mt(a,b) memset(a,b,sizeof(a))
using namespace std;
typedef long long LL;
const double pi=acos(-1.0);
const double eps=1e-8;
const int inf=0x3f3f3f3f;
const int M=2e5+10;
int n;
int a[M];
bool tabu[M];
int du[M];
queue<int> q;
void init(){
    for(int i=1;i<=n;i++){
        tabu[i]=false;
        du[i]=0;
    }
    for(int i=1;i<=n;i++){
        du[a[i]]++;
    }
    while(!q.empty()) q.pop();
    for(int i=1;i<=n;i++){
        if(du[i]==0) q.push(i);
    }
    while(!q.empty()){
        int u=q.front();
        q.pop();

        #ifdef debug
        printf("front =  %d
",u);
        #endif // debug

        tabu[u]=true;
        du[a[u]]--;
        if(du[a[u]]==0){
            q.push(a[u]);
        }
    }
}
int solve(){
    init();
    #ifdef debug
    for(int i=1;i<=n;i++){
        printf("%d ",tabu[i]);
    }
    puts("");
    #endif // debug
    int sum=0;
    int root=-1;
    for(int i=1;i<=n;i++){
        if(a[i]==i){
            root=i;
            tabu[i]=true;
            break;
        }
    }
    if(root==-1){
        for(int i=1;i<=n;i++){
            if(tabu[i]) continue;
            root=i;
            while(true){
                tabu[a[i]]=true;
                i=a[i];
                if(i==root) break;
            }
            a[i]=i;
            sum++;
            break;
        }
    }
    for(int i=1;i<=n;i++){
        if(tabu[i]) continue;
        int s=i,t=i;
        while(true){
            tabu[a[t]]=true;
            t=a[t];
            if(t==s) break;
        }
        a[s]=root;
        sum++;
    }
    return sum;
}
int main(){
    #ifdef txtout
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
    #endif // txtout
    while(~scanf("%d",&n)){
        for(int i=1;i<=n;i++){
            scanf("%d",&a[i]);
        }
        printf("%d
",solve());
        for(int i=1;i<=n;i++){
            printf("%d%c",a[i],i==n?'
':' ');
        }
    }
    return 0;
}

end