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// interactor.cpp
// Build: g++ -std=gnu++17 -O2 -pipe -static -s interactor.cpp -o interactor
// Run : interactor <input> <output> <answer> [--seed=...]
// input: one line "n s"
// Protocol:
// - Player output: walk x (0 <= x <= 1e9) -- Interactor responds: label[pos]
// - Player output: guess g -- Terminates; if g==n then score by q, otherwise score 0
//
// Rules:
// - Initial: label[s]=s, used set = {s}
// - When walking to position pos that hasn't been assigned: repeatedly random r in [1..n] until r not in used, then label[pos]=r, add r to used
// - Maximum walk count MAX_Q=200000
//
// Scoring: f(q) is log10 space piecewise linear interpolation:
// (1,100), (10000,95), (20000,60), (50000,30), extrapolated to 0 at 200000
// Correct: quitp(f/100), wrong: quitp(0)
#include "testlib.h"
#include <bits/stdc++.h>
using namespace std;
static const long long MAX_Q = 200000LL;
// Continuous, monotonically decreasing, log10 piecewise linear interpolation
static double score_from_queries(long long q) {
if (q <= 1) return 100.0;
const double t = log10((double)q);
const double t1 = 0.0; // log10(1)
const double t2 = 4.0; // log10(10000)
const double t3 = log10(20000.0); // ~4.30103
const double t4 = log10(50000.0); // ~4.69897
const double t5 = log10(200000.0); // ~5.30103
auto lerp = [](double a, double b, double x, double xa, double xb) {
if (xa == xb) return a;
double w = (x - xa) / (xb - xa);
return a + (b - a) * w;
};
if (t <= t2) return lerp(100.0, 95.0, t, t1, t2);
else if (t <= t3) return lerp(95.0, 60.0, t, t2, t3);
else if (t <= t4) return lerp(60.0, 30.0, t, t3, t4);
else if (t <= t5) return max(0.0, lerp(30.0, 0.0, t, t4, t5));
else return 0.0;
}
int main(int argc, char* argv[]) {
registerInteraction(argc, argv);
// Read n, s
long long n = inf.readLong(1LL, 1000000000LL, "n");
long long s = inf.readLong(1LL, n, "s");
long long pos = s;
long long qcnt = 0;
// Node -> visible value; assigned only on first visit to node
unordered_map<long long, long long> label;
label.reserve(1 << 16);
label.max_load_factor(0.7f);
// Set of used numbers to avoid duplicates
unordered_set<long long> used;
used.reserve(1 << 16);
used.max_load_factor(0.7f);
// Initialize
label[s] = s;
used.insert(s);
// Sample an unused random number (n is large, expected attempts is low)
auto take_random_unused_number = [&]() -> long long {
while (true) {
long long r = rnd.next(1LL, n);
if (!used.count(r)) {
used.insert(r);
return r;
}
}
};
auto tell = [&](long long v) {
cout << v << '\n' << flush;
};
while (true) {
string cmd = ouf.readWord(); // Read a word (non-whitespace characters)
if (cmd == "walk") {
long long x = ouf.readLong(0LL, 1000000000LL, "x");
// cerr<<x<<"\n";
long long step = (n == 1 ? 0 : (x % n));
pos = ((pos - 1 + step) % n) + 1;
if (!label.count(pos)) {
long long val = take_random_unused_number();
label[pos] = val;
}
++qcnt;
if (qcnt > MAX_Q) {
quitf(_wa, "Too many queries: %lld (max %lld)", qcnt, MAX_Q);
}
tell(label[pos]);
} else if (cmd == "guess") {
long long g = ouf.readLong(1LL, 1000000000LL, "n_guess");
bool ok = (g == n);
if (!ok) {
quitp(0.0, "Wrong answer. hidden n=%lld, your guess=%lld, queries=%lld", n, g, qcnt);
} else {
double score = score_from_queries(qcnt);
double part = max(0.0, min(100.0, score)) / 100.0;
double unbounded_part = max(0.0, score) / 100.0;
quitp(part, "OK. n=%lld, queries=%lld, Ratio: %.4f, RatioUnbounded: %.4f", n, qcnt, part, unbounded_part);
}
} else {
quitf(_wa, "Unknown command: '%s' (expected 'walk' or 'guess')", cmd.c_str());
}
}
}
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