Submission #827722

#	Time	Username	Problem	Language	Result	Execution time	Memory
827722		nnin	Aliens (IOI07_aliens)	C++14	0 / 100	1 ms	208 KiB

aliens

#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
using namespace std;

int n, x, y, m;

bool interact(int xx, int yy) {
    if(xx==x && yy==y) return 1;
    printf("examine %d %d\n", xx, yy);
    string s;
    cin>>s;
    return s[0]=='t';
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin>>n>>x>>y;
    int l, r, two;

    two = 1;
    while(x+two<=n && interact(x+two, y)) two *= 2;
    l = x+(two/2);
    r = min(x+two, n);
    while(l<r) {
        int mid = (l+r+1)/2;
        if(interact(mid, y)) l = mid;
        else r = mid-1;
    }
    int right = l;

    two = 1;
    while(x-two>=1 && interact(x-two, y)) two *= 2;
    l = max(x-two, 1);
    r = x-(two/2);
    while(l<r) {
        int mid = (l+r)/2;
        if(interact(mid, y)) r = mid;
        else l = mid+1;
    }
    int left = l;

    two = 1;
    while(y+two<=n && interact(x, y+two)) two *= 2;
    l = y+(two/2);
    r = min(y+two, n);
    while(l<r) {
        int mid = (l+r+1)/2;
        if(interact(x, mid)) l = mid;
        else r = mid-1;
    }
    int top = l;

    two = 1;
    while(y-two>=1 && interact(x, y-two)) two *= 2;
    l = max(y-two, 1);
    r = y-(two/2);
    while(l<r) {
        int mid = (l+r)/2;
        if(interact(x, mid)) r = mid;
        else l = mid+1;
    }
    int bottom = l;

    m = right+1-left;
    int xc = (left+right)/2;
    int yc = (top+bottom)/2;

    if(xc+(4*m)<=n && interact(xc+(4*m), yc)) {
        xc += 2*m;
        if(yc+(4*m)<=n && interact(xc, yc+(4*m))) {
            yc += 2*m;
        } else if(yc-(4*m)>=1 && interact(xc, yc-(4*m))) {
            yc -= 2*m;
        }
    } else if(xc-(4*m)>=1 && interact(xc-(4*m), yc)) {
        xc -= 2*m;
        if(yc+(4*m)<=n && interact(xc, yc+(4*m))) {
            yc += 2*m;
        } else if(yc-(4*m)>=1 && interact(xc, yc-(4*m))) {
            yc -= 2*m;
        }
    } else if(xc+(2*m)<=n && xc-(2*m)>=1) {
        bool bl = interact(xc-(2*m), yc);
        bool br = interact(xc+(2*m), yc);
        if(bl && !br) {
            xc -= m;
            if(yc+(3*m)<=n && interact(xc, yc+(3*m))) {
                yc += m;
            } else if(yc-(3*m)>=1 && interact(xc, yc-(3*m))) {
                yc -= m;
            }
        } else if(br && !bl) {
            xc += m;
            if(yc+(3*m)<=n && interact(xc, yc+(3*m))) {
                yc += m;
            } else if(yc-(3*m)>=1 && interact(xc, yc-(3*m))) {
                yc -= m;
            }
        }
    }

    printf("solution %d %d", xc, yc);
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10