Submission #73637

#	Time	Username	Problem	Language	Result	Execution time	Memory
73637		top34051	Hotter Colder (IOI10_hottercolder)	C++17	89 / 100	726 ms	8216 KiB

hottercolder

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

int n,rev;

int kuy(int x) {
    if(!rev) return x;
    return n-x+1;
}

int small(int l, int r, int a) {
    Guess(kuy(l));
    int res=Guess(kuy(r));
//    printf("res = %d\n",res);
    if (res==0) return (l+r)/2;
    if (res==1)  return r;
    return l;
}

int solve(int l, int r, int a) {
//    printf("solve [%d, %d] : %d [%d, %d]\n",kuy(l),kuy(r),a,l,r);
    if(l==r) return l;
    if(r-l+1<=3) return small(l,r,a);
    if(a==l) {
        int b = (l*2+r)/3;
        int c = (l+2*r)/3;
        int tmp1 = Guess(kuy(b)), tmp2 = Guess(kuy(c));
//        printf("b = %d c = %d tmp = %d and %d (%d, %d)\n",kuy(b),kuy(c),tmp1,tmp2,b,c);
        if(a!=b && tmp1==0) return (a+b)/2;
        if(b!=c && tmp2==0) return (b+c)/2;
        if(tmp2==-1) {
            if(tmp1==-1) return solve(l,(a+b)/2,c);
            else return solve((a+b)/2+1,(b+c)/2,c);
        }
        else return solve((b+c)/2+1,r,c);
    }
    else if(l<=a && a<=r) {
        int b = (l+2*r)/3;
        int tmp = Guess(kuy(b));
//        printf("b = %d (%d)\n",kuy(b),b);
        if(a!=b && tmp==0) return (a+b)/2;
        if(tmp==-1) return solve(l,(a+b)/2,b);
        else return solve((a+b)/2+1,r,b);
    }
    else {
        int b = l+r-a;
        if(b<1) b = 1;
        if(b>n) b = n;
//        printf("b = %d (%d)\n",kuy(b),b);
        int tmp = Guess(kuy(b));
        if(a!=b && tmp==0) return (a+b)/2;
        if(b < a) {
            if(tmp==1) return solve(l,(l+r)/2,b);
            return solve((l+r)/2,r,b);
        }
        else {
            if(tmp==1) return solve((l+r)/2,r,b);
            return solve(l,(l+r)/2,b);
        }
    }
}

int solve2(int n) {
    int l = 1;
    int r = n;
    Guess(1);
    int p = 1;
    while (l < r) {
        int z = r-l+1;
        int res, side;
        if (p == l) {
            res = Guess(p = r), side = 0;
        } else if (p == r) {
            res = Guess(p = l), side = 1;
        } else if (p < l) {
            int q = r+(l-p);
            if (q <= n) {
                res = Guess(p = q);
                side = 0;
            } else {
                Guess(p = (r <= n/2 ? r : l));
                continue;
            }
        } else if (p > r) {
            int q = l-(p-r);
            if (q >= 1) {
                res = Guess(p = q);
                side = 1;
            } else {
                Guess(p = (r <= n/2 ? r : l));
                continue;
            }
        } else {
            assert(false);
        }

        int m = (l+r)/2;
        if (side == 0) {
            if (z % 2 == 0) {
                if (res == 1) l = m+1;
                else if (res == -1) r = m;
                else assert(false);
            } else {
                if (res == 1) l = m+1;
                else if (res == -1) r = m-1;
                else l = r = m;
            }
        } else {
            if (z % 2 == 0) {
                if (res == 1) r = m;
                else if (res == -1) l = m+1;
                else assert(false);
            } else {
                if (res == 1) r = m-1;
                else if (res == -1) l = m+1;
                else l = r = m;
            }
        }
    }
    return l;
}

int HC(int N) {
    if(N<=1000000) return solve2(N);
    n = N;
    Guess(N);
    int tmp = Guess(1);
    if(tmp==0) return (1+N)/2;
    rev = 0;
    if(tmp==1) rev = 1;
//    printf("rev = %d\n",rev);
    if(rev) Guess(N);
    return kuy(solve(1,N,1));
}

• Subtask 1: 25 / 25
• Subtask 2: 25 / 25
• Subtask 3: 25 / 25
• Subtask 4: 14 / 25