oj.uz

Submission #159264

# Submission time Handle Problem Language Result Execution time Memory
159264 2019-10-21T17:36:01 Z ppnxblstr Alternating Current (BOI18_alternating) C++14
19 / 100
 61 ms 6392 KB 
#include<bits/stdc++.h>
using namespace std;
int main()
{
  int i,j,n,m,l,r,t=0,y,z,s=0,u,v,a=-1,b,tail,htail,cmm,full;
  scanf("%d %d\n",&n,&m);

  int reci[m]={},recf[m]={};
  int ans[m]={};
  int count[n]={};
  int alert[n]={};
  int st[n]={},en[n]={};
  int pin[n]={};
  int pinsort[m]={};
  for(i=0;i<n;i++)
  {
    pin[i]--;
  }
  for(i=0;i<m;i++)
  {
    scanf("%d %d",&l,&r);
    st[l-1]++;
    en[r-1]++;
    reci[i]=l-1;
    if(l>r)
    {count[n-1]++;}
    else if(r==n)
    {count[n-1]++;}
    recf[i]=r-1;
    if(pin[r-1]==-1)
    {pin[r-1]=i;s++;}
  }
  for(i=0;i<n-1;i++)
  {
    if(i==0)
    {
      count[0]=count[n-1]+st[0]-en[n-1];
    }
    else
    {
      count[i]=count[i-1]+st[i]-en[i-1];
    }
  }
  for(i=0;i<n;i++)
  {
    if(count[i]<2)
    {printf("impossible");return 0;}
    if(count[i]==2)
    {alert[t]=i;t++;}
  }
  y=0;
  z=0;
  if(t!=0)
  {
    for(i=alert[t-1]+1;i<=n+alert[t-1];i++)
    {
      j=i%n;
      z+=st[j];
      if(z>=2)
      {break;}
      if(j==alert[y])
      {
        y++;z=0;
      }
    }
  }
  int hi[s]={};
  j=0;
  i=0;
  while(j<s)
  {
    if(pin[i]!=-1)
    {
      hi[j]=pin[i];
      j++;
    }
    i++;
  }
  int gi[s]={};
  int ad[s]={};
  int rehi[n]={};
  for(i=0;i<s;i++)
  {
    rehi[recf[hi[i]]]=i;
  }
  gi[0]=0;
  for(i=1;i<s;i++)
  {
    gi[i]=gi[i-1]+en[recf[hi[i-1]]];
  }
  for(i=0;i<m;i++)
  {
    u=rehi[recf[i]];
    v=gi[u]+ad[u];
    pinsort[v]=i;
    ad[u]++;
  }
  if(t==0)
  {
    cmm=n-1;
    int mst=n,mnd=n;
    for(i=0;i<m;i++)
    {
      if(recf[i]==n-1||recf[i]<reci[i])
      {
        if(reci[i]<mst)
        {
          b=a;
          a=i;
          mnd=mst;
          mst=recf[i];
        }
        else if(reci[i]<mnd)
        {
          b=i;
          mnd=recf[i];
        }
      }
    }
  }
  else if(y==t)
  {
    cmm=alert[0];
    for(i=0;i<m;i++)
    {
      if(reci[i]<=alert[0]&&recf[i]>=alert[0]||reci[i]>recf[i]&&(reci[i]<=alert[0]||recf[i]>=alert[0]))
      {
        if(a==-1)
        {
          a=i;
        }
        else
        {
          b=i;
        }
      }
    }
    for(tail=t-1;tail>0;tail--)
    {
      if((alert[tail]<reci[a]||reci[a]<=alert[0])&&(alert[tail]<reci[b]||reci[b]<=alert[0]))
      {
        tail++;
        break;
      }
    }
    if(alert[tail]>=reci[a]&&reci[a]>alert[0])
    {
      htail=1;
    }
    else
    {
      htail=2;
    }
  }
  else
  {
    cmm=alert[y];
    for(i=0;i<m;i++)
    {
      if(reci[i]<=alert[y]&&recf[i]>=alert[y]||reci[i]>recf[i]&&(reci[i]<=alert[y]||recf[i]>=alert[y]))
      {
        if(a==-1)
        {
          a=i;
        }
        else
        {
          b=i;
        }
      }
    }
  }
  ans[a]=1;
  ans[b]=2;
  int in2,fi2,in1,fi1,di2,di1,dic2,dic1,i1,i2,ff1,ff2;
  in2=reci[b];
  in1=reci[a];
  fi2=recf[b];
  fi1=recf[a];
  di2=(fi2-in2+n+1)%n;
  di1=(fi1-in1+n+1)%n;
  dic2=di2;
  dic1=di1;
  i1=0;
  i2=0;
  if(di1==0)
  {
    for(i=0;i<m;i++)
    {
      printf("%d",ans[i]%2);
    }
    return 0;
  }
  if(di2==0)
  {
    for(i=0;i<m;i++)
    {
      printf("%d",ans[i]/2);
    }
    return 0;
  }
  while(true)
  {
    if((fi2-cmm+n)%n>=(fi1-cmm+n)%n)
    {
      i1=(i1+1)%m;
      ff1=(fi1+1)%n;
      if(ans[pinsort[i1]]!=0)
      {
        continue;
      }
      if(ff1>=reci[pinsort[i1]]&&ff1<=recf[pinsort[i1]]||reci[pinsort[i1]]>recf[pinsort[i1]]&&(reci[pinsort[i1]]<=ff1||recf[pinsort[i1]]>=ff1))
      {
        ans[pinsort[i1]]=1;
        fi1=recf[pinsort[i1]];
        di1=(fi1-in1+n+1)%n;
        if(di1<=dic1)
        {
          full=1;
          break;
        }
        dic1=di1;
      }

    }
    else
    {
      i2=(i2+1)%m;
      ff2=(fi2+1)%n;
      if(ans[pinsort[i2]]!=0)
      {
        continue;
      }
      if(ff2>=reci[pinsort[i2]]&&ff2<=recf[pinsort[i2]]||reci[pinsort[i2]]>recf[pinsort[i2]]&&(reci[pinsort[i2]]<=ff2||recf[pinsort[i2]]>=ff2))
      {
        ans[pinsort[i2]]=2;
        fi2=recf[pinsort[i2]];
        di2=(fi2-in2+n+1)%n;
        if(di2<=dic2)
        {
          full=2;
          break;
        }
        dic2=di2;
      }
    }
  }
  if(t!=0&&y==t)
  {
    int lch1=-1,lch2;
    for(i=0;i<m;i++)
      {
        if(reci[i]<=alert[tail]&&recf[i]>=alert[tail]||reci[i]>recf[i]&&(reci[i]<=alert[tail]||recf[i]>=alert[tail]))
        {
          if(lch1!=-1)
          {
            lch2=i;
            break;
          }
          lch1=i;
        }
      }
    if(ans[lch1]==ans[lch2])
    {
      printf("impossible");
    }
  }
  if(full==1)
  {
    for(i=0;i<m;i++)
    {
      printf("%d",ans[i]%2);
    }
    return 0;
  }
  if(full==2)
  {
    for(i=0;i<m;i++)
    {
      printf("%d",ans[i]/2);
    }
    return 0;
  }
}

Compilation message

alternating.cpp: In function 'int main()':
alternating.cpp:126:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
       if(reci[i]<=alert[0]&&recf[i]>=alert[0]||reci[i]>recf[i]&&(reci[i]<=alert[0]||recf[i]>=alert[0]))
          ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
alternating.cpp:160:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
       if(reci[i]<=alert[y]&&recf[i]>=alert[y]||reci[i]>recf[i]&&(reci[i]<=alert[y]||recf[i]>=alert[y]))
          ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
alternating.cpp:212:32: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
       if(ff1>=reci[pinsort[i1]]&&ff1<=recf[pinsort[i1]]||reci[pinsort[i1]]>recf[pinsort[i1]]&&(reci[pinsort[i1]]<=ff1||recf[pinsort[i1]]>=ff1))
          ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
alternating.cpp:234:32: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
       if(ff2>=reci[pinsort[i2]]&&ff2<=recf[pinsort[i2]]||reci[pinsort[i2]]>recf[pinsort[i2]]&&(reci[pinsort[i2]]<=ff2||recf[pinsort[i2]]>=ff2))
          ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
alternating.cpp:253:32: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
         if(reci[i]<=alert[tail]&&recf[i]>=alert[tail]||reci[i]>recf[i]&&(reci[i]<=alert[tail]||recf[i]>=alert[tail]))
            ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
alternating.cpp:5:47: warning: variable 'htail' set but not used [-Wunused-but-set-variable]
   int i,j,n,m,l,r,t=0,y,z,s=0,u,v,a=-1,b,tail,htail,cmm,full;
                                               ^~~~~
alternating.cpp:6:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d\n",&n,&m);
   ~~~~~^~~~~~~~~~~~~~~~~
alternating.cpp:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&l,&r);
     ~~~~~^~~~~~~~~~~~~~~
alternating.cpp:263:27: warning: 'lch2' may be used uninitialized in this function [-Wmaybe-uninitialized]
     if(ans[lch1]==ans[lch2])
                   ~~~~~~~~^
alternating.cpp:253:31: warning: 'tail' may be used uninitialized in this function [-Wmaybe-uninitialized]
         if(reci[i]<=alert[tail]&&recf[i]>=alert[tail]||reci[i]>recf[i]&&(reci[i]<=alert[tail]||recf[i]>=alert[tail]))
                     ~~~~~~~~~~^
alternating.cpp:176:6: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
   in2=reci[b];
   ~~~^~~~~~~~

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 256 KB Output is correct
4 Correct 2 ms 128 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Incorrect 2 ms 256 KB no wires in direction 0 between segments 1 and 2
7 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 256 KB Output is correct
4 Correct 2 ms 128 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Incorrect 2 ms 256 KB no wires in direction 0 between segments 1 and 2
7 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 256 KB Output is correct
4 Correct 2 ms 128 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Incorrect 2 ms 256 KB no wires in direction 0 between segments 1 and 2
7 Halted 0 ms 0 KB -

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 33 ms 5140 KB Output is correct
2 Correct 5 ms 2680 KB Output is correct
3 Correct 16 ms 3576 KB Output is correct
4 Correct 21 ms 4600 KB Output is correct
5 Correct 54 ms 6264 KB Output is correct
6 Correct 40 ms 5112 KB Output is correct
7 Correct 55 ms 6140 KB Output is correct
8 Correct 7 ms 2684 KB Output is correct
9 Correct 5 ms 2552 KB Output is correct
10 Correct 55 ms 6392 KB Output is correct
11 Correct 41 ms 5496 KB Output is correct
12 Correct 45 ms 6252 KB Output is correct
13 Correct 4 ms 2296 KB Output is correct
14 Correct 4 ms 2296 KB Output is correct
15 Correct 49 ms 6140 KB Output is correct
16 Correct 16 ms 3576 KB Output is correct
17 Correct 61 ms 6140 KB Output is correct
18 Correct 36 ms 3192 KB Output is correct
19 Correct 6 ms 2424 KB Output is correct
20 Correct 38 ms 4856 KB Output is correct

Subtask #5
0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 256 KB Output is correct
4 Correct 2 ms 128 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Incorrect 2 ms 256 KB no wires in direction 0 between segments 1 and 2
7 Halted 0 ms 0 KB -