Submission #432224

#	Time	Username	Problem	Language	Result	Execution time	Memory
432224		juggernaut	Teleporters (IOI08_teleporters)	C++17	100 / 100	515 ms	28836 KiB

teleporters

#include<bits/stdc++.h>
#define fr first
#define sc second
using namespace std;
void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
typedef long long ll;
#define USING_ORDERED_SET 0
#if USING_ORDERED_SET
#include<bits/extc++.h>
using namespace __gnu_pbds;
template<class T>using ordered_set=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
#endif
template<class T>void umax(T &a,T b){if(a<b)a=b;}
template<class T>void umin(T &a,T b){if(b<a)a=b;}
#ifdef IOI2021SG
    #define printl(args...)printf(args)
#else
    #define printl(args...)((void)0)
#endif
int n,m,cnt;
int to[2000005];
bool vis[2000005];
void go(int v){
    while(true){
        if(v>2000001||vis[v])break;
        vis[v]=true;
        v++;
        if(to[v]){
            v=to[v];
            cnt++;
        }
    }
}
int main(){
    scanf("%d%d",&n,&m);
    while(n--){
        int x,y;
        scanf("%d%d",&x,&y);
        to[x]=y;
        to[y]=x;
    }
    int res=0;
    vector<int>v;
    for(int i=0;i<=2000001;i++)if(!vis[i]){
        cnt=0;
        go(i);
        if(i==0)res=cnt;
        else v.push_back(cnt);
    }
    sort(v.rbegin(),v.rend());
    for(int i=0;i<v.size()&&m--;i++){
        res+=v[i]+2;
    }
    m=max(m,0);
    res+=(m&1);
    m>>=1;
    res+=(m<<2);
    printf("%d",res);
}

Compilation message (stderr)

teleporters.cpp: In function 'int main()':
teleporters.cpp:51:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |     for(int i=0;i<v.size()&&m--;i++){
      |                 ~^~~~~~~~~
teleporters.cpp: In function 'void usaco(std::string)':
teleporters.cpp:5:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
teleporters.cpp:5:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
      |                                                           ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
teleporters.cpp: In function 'int main()':
teleporters.cpp:35:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
teleporters.cpp:38:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         scanf("%d%d",&x,&y);
      |         ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5