Submission #865702

#	Time	Username	Problem	Language	Result	Execution time	Memory
865702		jk410	Jousting tournament (IOI12_tournament)	C++17	49 / 100	1058 ms	1996 KiB

tournament

using namespace std;
int N;
int Tree[1<<18];
int A[100000];
int init(int l,int r,int n){
    if (l==r)
        return Tree[n]=1;
    int m=(l+r)>>1;
    return Tree[n]=init(l,m,n<<1)+init(m+1,r,n<<1|1);
}
void propagate(int l,int r,int n){
    if (l<r&&!Tree[n])
        Tree[n<<1]=Tree[n<<1|1]=0;
}
int query(int x,int l,int r,int n){
    propagate(l,r,n);
    if (l==r){
        if (x==1)
            return l;
        return l+1;
    }
    int m=(l+r)>>1;
    if (Tree[n<<1]<x)
        return query(x-Tree[n<<1],m+1,r,n<<1|1);
    return query(x,l,m,n<<1);
}
int update(int lx,int rx,int l,int r,int n){
    propagate(l,r,n);
    if (r<lx||rx<l)
        return Tree[n];
    if (lx<=l&&r<=rx)
        return Tree[n]=0;
    int m=(l+r)>>1;
    return Tree[n]=update(lx,rx,l,m,n<<1)+update(lx,rx,m+1,r,n<<1|1);
}
int GetBestPosition(int _N, int C, int R, int *K, int *S, int *E){
    N=_N;
    init(0,N-1,1);
    for (int i=0; i<C; i++){
        int l=query(S[i]+1,0,N-1,1);
        int r=query(E[i]+2,0,N-1,1)-1;
        S[i]=l;
        E[i]=r;
        update(l+1,r,0,N-1,1);
    }
    int mxCnt=-1,ans;
    for (int t=0; t<N; t++){
        for (int i=0; i<t; i++)
            A[i]=K[i];
        A[t]=R;
        for (int i=t+1; i<N; i++)
            A[i]=K[i-1];
        int l=t,r=t;
        while (l&&A[l-1]<A[t])
            l--;
        while (r+1<N&&A[r+1]<A[t])
            r++;
        int cnt=0;
        for (int i=0; i<C; i++){
            if (S[i]<=t&&t<=E[i]){
                if (S[i]<l||r<E[i])
                    break;
                cnt++;
            }
        }
        if (mxCnt<cnt){
            mxCnt=cnt;
            ans=t;
        }
    }
    return ans;
}

Compilation message (stderr)

tournament.cpp: In function 'int GetBestPosition(int, int, int, int*, int*, int*)':
tournament.cpp:71:12: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   71 |     return ans;
      |            ^~~

• Subtask 1: 17 / 17
• Subtask 2: 32 / 32
• Subtask 3: 0 / 51