Submission #91672

#	Time	Username	Problem	Language	Result	Execution time	Memory
91672		ics0503	Aliens (IOI07_aliens)	C++17	100 / 100	3 ms	380 KiB

aliens

#include<stdio.h>
#include<string.h>
long long min(long long a, long long b) { if (a < b)return a; return b; }
bool qr(long long x, long long y) {
	printf("examine %lld %lld\n", x, y);
	fflush(stdout);
	char X[10]; scanf("%s", X);
	if (strcmp(X, "true") == 0)return 1; return 0;
}
void sol(long long x, long long y) {
	printf("solution %lld %lld\n", x, y);
	fflush(stdout);
}
int main() {
	long long n, x0, y0; scanf("%lld%lld%lld", &n, &x0, &y0);
	long long sx, sy, ex, ey, i, j, bef;
	bef = x0;
	for (i = 0;; i++) {
		long long x = x0 + (1ll << i);
		if (x > n)x = n;
		if (x == n || qr(x, y0) == 0) {
			long long s = bef, e = x;
			while (s <= e) {
				long long m = (s + e) / 2;
				if (qr(m, y0))s = m + 1, ex = m;
				else e = m - 1;
			}
			break;
		}
		bef = x;
	}
	bef = y0;
	for (i = 0;; i++) {
		long long y = y0 + (1ll << i);
		if (y > n)y = n;
		if (y == n || qr(x0, y) == 0) {
			long long s = bef, e = y;
			while (s <= e) {
				long long m = (s + e) / 2;
				if (qr(x0, m))s = m + 1, ey = m;
				else e = m - 1;
			}
			break;
		}
		bef = y;
	}
	bef = x0;
	for (i = 0;; i++) {
		long long x = x0 - (1ll << i);
		if (x <= 0)x = 1;
		if (x == 1 || qr(x, y0) == 0) {
			long long s = x, e = bef;
			while (s <= e) {
				long long m = (s + e) / 2;
				if (qr(m, y0))e = m - 1, sx = m;
				else s = m + 1;
			}
			break;
		}
		bef = x;
	}
	bef = y0;
	for (i = 0;; i++) {
		long long y = y0 - (1ll << i);
		if (y <= 0)y = 1;
		if (y == 1 || qr(x0, y) == 0) {
			long long s = y, e = bef;
			while (s <= e) {
				long long m = (s + e) / 2;
				if (qr(x0, m))e = m - 1, sy = m;
				else s = m + 1;
			}
			break;
		}
		bef = y;
	}
	long long m = (ex - sx + 1);
	while (sx>m&&sy>m&&qr(sx - m, sy - m))sx -= m, sy -= m, ex -= m, ey -= m;
	while (sx>2*m&&qr(sx - 2 * m, sy))sx -= 2 * m, ex -= 2 * m;
	while (sy>2*m&&qr(sx, sy - 2 * m))sy -= 2 * m, ey -= 2 * m;
	sol((2 * sx + 5 * m - 1) / 2, (2 * sy + 5 * m - 1) / 2);
	return 0;
}

Compilation message (stderr)

aliens.cpp: In function 'bool qr(long long int, long long int)':
aliens.cpp:8:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if (strcmp(X, "true") == 0)return 1; return 0;
  ^~
aliens.cpp:8:39: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  if (strcmp(X, "true") == 0)return 1; return 0;
                                       ^~~~~~
aliens.cpp: In function 'int main()':
aliens.cpp:16:31: warning: unused variable 'j' [-Wunused-variable]
  long long sx, sy, ex, ey, i, j, bef;
                               ^
aliens.cpp: In function 'bool qr(long long int, long long int)':
aliens.cpp:7:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  char X[10]; scanf("%s", X);
              ~~~~~^~~~~~~~~
aliens.cpp: In function 'int main()':
aliens.cpp:15:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  long long n, x0, y0; scanf("%lld%lld%lld", &n, &x0, &y0);
                       ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aliens.cpp:16:16: warning: 'sy' may be used uninitialized in this function [-Wmaybe-uninitialized]
  long long sx, sy, ex, ey, i, j, bef;
                ^~
aliens.cpp:77:20: warning: 'sx' may be used uninitialized in this function [-Wmaybe-uninitialized]
  long long m = (ex - sx + 1);
                 ~~~^~~~
aliens.cpp:77:20: warning: 'ex' may be used uninitialized in this function [-Wmaybe-uninitialized]

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