Submission #197329

#	Time	Username	Problem	Language	Result	Execution time	Memory
197329		arnold518	Aliens (IOI07_aliens)	C++14	40 / 100	3063 ms	508 KiB

aliens

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

struct Point { ll x, y; };

ll N, M, MM;
Point S;

bool query(Point p)
{
	if(!(1<=p.x && p.x<=N && 1<=p.y && p.y<=N)) return false;
	printf("examine %d %d\n", p.x, p.y);
	fflush(stdout);

	char t[10];
	scanf("%s", t);
	return t[0]=='t';
}

void answer(Point p)
{
	printf("solution %d %d\n", p.x, p.y);
	fflush(stdout);
	exit(0);
}

int main()
{
	ll i, j;

	scanf("%lld%lld%lld", &N, &S.x, &S.y);

	ll l, r;

	ll lo=S.x, hi=N+1;
	while(lo+1<hi)
	{
		ll mid=lo+hi>>1;
		if(query({mid, S.y})) lo=mid;
		else hi=mid;
	}
	r=lo;

	lo=0, hi=S.x;
	while(lo+1<hi)
	{
		ll mid=lo+hi>>1;
		if(query({mid, S.y})) hi=mid;
		else lo=mid;
	}
	l=hi;

	if(!query({l+r>>1, S.y})) MM=(r-l+1)/3;
	else
	{
		if((r-l+1)%5==0 && !query({l+(r-l+1)/5, S.y})) MM=(r-l+1)/5;
		else MM=r-l+1;
	}

	for(i=S.x; i<N; i++) if(!query({i+1, S.y})) break; r=i;
	for(i=S.x; i>1; i--) if(!query({i-1, S.y})) break; l=i;
	M=r-l+1; S.x=(l+r)/2;

	for(i=S.y; i<N; i++) if(!query({S.x, i+1})) break; r=i;
	for(i=S.y; i>1; i--) if(!query({S.x, i-1})) break; l=i;
	S.y=(l+r)/2;
	
	assert(M==MM);

	int p1, p2, p3, p4;
	p1=query({S.x, S.y+M+M});
	p2=query({S.x+M+M, S.y});
	p3=query({S.x, S.y-M-M});
	p4=query({S.x-M-M, S.y});

	if(p1 && p2 && p3 && p4) answer({S.x, S.y});
	if(p1 && p2 && p3 && !p4) answer({S.x+M+M, S.y});
	if(!p1 && p2 && p3 && p4) answer({S.x, S.y-M-M});
	if(p1 && !p2 && p3 && p4) answer({S.x-M-M, S.y});
	if(p1 && p2 && !p3 && p4) answer({S.x, S.y+M+M});

	if(p1 && p2)
	{
		if(query({S.x-M, S.y-M})) answer({S.x+M, S.y+M});
		else answer({S.x+M+M, S.y+M+M});
	}
	if(p2 && p3)
	{
		if(query({S.x-M, S.y+M})) answer({S.x+M, S.y-M});
		else answer({S.x+M+M, S.y-M-M});
	}
	if(p3 && p4)
	{
		if(query({S.x+M, S.y+M})) answer({S.x-M, S.y-M});
		else answer({S.x-M-M, S.y-M-M});
	}
	if(p4 && p1)
	{
		if(query({S.x+M, S.y-M})) answer({S.x-M, S.y+M});
		else answer({S.x-M-M, S.y+M+M});
	}
}

Compilation message (stderr)

aliens.cpp: In function 'bool query(Point)':
aliens.cpp:16:36: warning: format '%d' expects argument of type 'int', but argument 2 has type 'll {aka long long int}' [-Wformat=]
  printf("examine %d %d\n", p.x, p.y);
                            ~~~     ^
aliens.cpp:16:36: warning: format '%d' expects argument of type 'int', but argument 3 has type 'll {aka long long int}' [-Wformat=]
aliens.cpp: In function 'void answer(Point)':
aliens.cpp:26:37: warning: format '%d' expects argument of type 'int', but argument 2 has type 'll {aka long long int}' [-Wformat=]
  printf("solution %d %d\n", p.x, p.y);
                             ~~~     ^
aliens.cpp:26:37: warning: format '%d' expects argument of type 'int', but argument 3 has type 'll {aka long long int}' [-Wformat=]
aliens.cpp: In function 'int main()':
aliens.cpp:42:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   ll mid=lo+hi>>1;
          ~~^~~
aliens.cpp:51:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   ll mid=lo+hi>>1;
          ~~^~~
aliens.cpp:57:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  if(!query({l+r>>1, S.y})) MM=(r-l+1)/3;
             ~^~
aliens.cpp:64:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=S.x; i<N; i++) if(!query({i+1, S.y})) break; r=i;
  ^~~
aliens.cpp:64:53: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  for(i=S.x; i<N; i++) if(!query({i+1, S.y})) break; r=i;
                                                     ^
aliens.cpp:65:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=S.x; i>1; i--) if(!query({i-1, S.y})) break; l=i;
  ^~~
aliens.cpp:65:53: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  for(i=S.x; i>1; i--) if(!query({i-1, S.y})) break; l=i;
                                                     ^
aliens.cpp:68:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=S.y; i<N; i++) if(!query({S.x, i+1})) break; r=i;
  ^~~
aliens.cpp:68:53: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  for(i=S.y; i<N; i++) if(!query({S.x, i+1})) break; r=i;
                                                     ^
aliens.cpp:69:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=S.y; i>1; i--) if(!query({S.x, i-1})) break; l=i;
  ^~~
aliens.cpp:69:53: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
  for(i=S.y; i>1; i--) if(!query({S.x, i-1})) break; l=i;
                                                     ^
aliens.cpp:33:8: warning: unused variable 'j' [-Wunused-variable]
  ll i, j;
        ^
aliens.cpp: In function 'bool query(Point)':
aliens.cpp:20:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", t);
  ~~~~~^~~~~~~~~
aliens.cpp: In function 'int main()':
aliens.cpp:35:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld%lld", &N, &S.x, &S.y);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 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