PAT 甲级 2017年冬季

1 PAT 甲级 1136 A Delayed Palindrome

#include <bits/stdc++.h>
using namespace std;
string a,b,c;
bool IsPali(string &s){
    int sz=s.size();
    for(int i=0;i<=sz/2;++i){
        if(s[i]!=s[sz-1-i]) return false;
    }
    return true;
}
string Add(string a,string b){
    string ret;
    reverse(a.begin(),a.end());
    reverse(b.begin(),b.end());
    while(a.size()<b.size()) a+='0';
    while(b.size()<a.size()) b+='0';
    int c=0,p1,p2;
    for(size_t i=0;i<a.size();++i){
        p1=a[i]-'0',p2=b[i]-'0';
        ret+=char((p1+p2+c)%10+'0');
        c=(p1+p2+c)/10;
    }
    if(c!=0) ret+=char(c+'0');
    reverse(ret.begin(),ret.end());
    return ret;
}
int main(){
    cin>>a;
    for(int i=0;i<10;++i){
        if(IsPali(a)) break;
        b=a;reverse(b.begin(),b.end());
        c=Add(a,b);
        cout<<a<<" + "<<b<<" = "<<c<<"\n";
        a=c;
    }
    if(IsPali(a)) cout<<a<<" is a palindromic number.";
    else cout<<"Not found in 10 iterations.";
}

2 PAT 甲级 1137 Final Grading

#include <bits/stdc++.h>
using namespace std;
int p,m,n;
struct Msg{
    int prog{-1},mid{-1},final{-1},g{-1};
    bool is_q{false};
    bool GetQ(){
        g=(mid>final?round((mid*40+final*60)/100.0):final);
        if(prog>=200&&g>=60) {is_q=true; return true;}
        return false;
    }
};
map<string,Msg> mp;
int main(){
    cin>>p>>m>>n;
    string id;int score;
    for(int i=0;i<p;++i) {cin>>id>>score; mp[id].prog=score;}
    for(int i=0;i<m;++i) {cin>>id>>score; mp[id].mid=score;}
    for(int i=0;i<n;++i) {cin>>id>>score; mp[id].final=score;}
    vector<string> ans;
    for(auto &i:mp){
        if(i.second.GetQ()) ans.push_back(i.first);
    }
    sort(ans.begin(),ans.end(),[](string &a,string &b){
        if(mp[a].g!=mp[b].g) return mp[a].g>mp[b].g;
        return a<b;
    });
    for(auto i:ans){
        Msg& t=mp[i];
        printf("%s %d %d %d %d\n",i.c_str(),t.prog,t.mid,t.final,t.g);
    }
}

3 PAT 甲级 1138 Postorder Traversal

#include <bits/stdc++.h>
using namespace std;
const int N=50010;
int in[N],pre[N];
bool done=false;
int Solve(int l1,int r1,int l2,int r2){
    if(l1>r1) return -1;
    int root=pre[l1],mid=l2;
    while(mid<r2&&in[mid]!=root) ++mid;
    int lc=Solve(l1+1,l1+mid-l2,l2,mid-1);
    int rc=Solve(l1+mid-l2+1,r1,mid+1,r2);
    if(lc==-1&&rc==-1&&!done) {cout<<root; done=true;}
    return root;
}
int main(){
    int n;scanf("%d",&n);
    for(int i=0;i<n;++i) scanf("%d",&pre[i]);
    for(int i=0;i<n;++i) scanf("%d",&in[i]);
    Solve(0,n-1,0,n-1);
}

4 PAT 甲级 1139 First Contact

#include <bits/stdc++.h>
using namespace std;
map<string,set<string>> graph;
vector<pair<string,string>> ans;
int main(){
    int n,m;cin>>n>>m;
    for(int i=0;i<m;++i){
        string a,b;cin>>a>>b;
        graph[a].insert(b);
        graph[b].insert(a);
    }
    int k;cin>>k;
    for(int i=0;i<k;++i){
        string a,b;cin>>a>>b;
        ans.clear();
        for(auto &f1:graph[a]){
            if(f1[0]=='-'&&a[0]!='-'||f1[0]!='-'&&a[0]=='-') continue;
            if(f1==b) continue;
            for(auto &f2:graph[f1]){
                if(f2[0]=='-'&&b[0]!='-'||f2[0]!='-'&&b[0]=='-') continue;
                if(f2==b||f2==a) continue;
                if(graph[f2].count(b)!=0){
                    string n1=f1,n2=f2;
                    if(f1[0]=='-') n1=n1.substr(1,4);
                    if(f2[0]=='-') n2=n2.substr(1,4);
                    ans.push_back(make_pair(n1,n2));
                }
            }
        }
        sort(ans.begin(),ans.end(),[](auto &a,auto &b){
            if(a.first!=b.first) return a.first<b.first;
            return a.second<b.second;
        });
        cout<<ans.size()<<"\n";
        for(auto p:ans){
            cout<<p.first<<" "<<p.second<<"\n";
        }
    }
}