Submission #632030

#	Time	Username	Problem	Language	Result	Execution time	Memory
632030		TimDee	Thousands Islands (IOI22_islands)	C++17	10 / 100	36 ms	5952 KiB

islands

#include "islands.h"
#include <bits/stdc++.h>
using namespace std;

int n,m;
vector<int> u,v;

variant<bool, std::vector<int>> find_journey(int N, int M, vector<int> U, vector<int> V) {

  n=N,m=M,u=U,v=V;
  if (n==2) {
    vector<int> fv,sv;
    for (int x=0; x<m; ++x) if (u[x]==0) fv.push_back(x); else sv.push_back(x);
      int f=fv.size(), s=sv.size();
    if (f>=2 && s) {
      vector<int> r={fv[0],sv[0],fv[1],fv[0],sv[0],fv[1]};;
      return r;
    } 
    else return false;
  }

  if (n<=400 && m==n*(n-1)) {

    int a,b,c,d; 
    for (int i=0; i<m; ++i) {
      if (u[i]==0 && v[i]==1) a=i;
      if (u[i]==0 && v[i]==2) b=i;
      if (u[i]==1 && v[i]==0) c=i;
      if (u[i]==2 && v[i]==0) d=i;
    }
    vector<int> r = {a,c,b,d,c,a,d,b};
    return r;

  }

}

Compilation message (stderr)

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:36:1: warning: control reaches end of non-void function [-Wreturn-type]
   36 | }
      | ^
islands.cpp:31:37: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
   31 |     vector<int> r = {a,c,b,d,c,a,d,b};
      |                                     ^
islands.cpp:31:37: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
islands.cpp:31:37: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
islands.cpp:31:37: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45