QOJ.ac
QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#393662 | #8554. Bot Friends | hos_lyric | TL | 17ms | 12028kb | C++14 | 4.9kb | 2024-04-19 03:11:55 | 2024-04-19 03:11:56 |
Judging History
answer
#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using Int = long long;
template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")
int brute(const string &S) {
const int N = S.size();
vector<int> dp(1 << (2*N+1), -1);
dp[0] = 0;
for (int p = 0; p < 1 << (2*N+1); ++p) if (~dp[p]) {
// bot i+0.5
for (int i = 0; i < N; ++i) if (!(p & 1 << (2*i+1))) {
if (S[i] == '?' || S[i] == '<') {
for (int j = i; ; --j) {
assert(j >= 0);
if (!(p & 1 << (2*j))) {
chmax(dp[p | 1 << (2*i+1) | 1 << (2*j)], dp[p] + ((j != i) ? 1 : 0));
break;
}
}
}
if (S[i] == '?' || S[i] == '>') {
for (int j = i + 1; ; ++j) {
assert(j <= N);
if (!(p & 1 << (2*j))) {
chmax(dp[p | 1 << (2*i+1) | 1 << (2*j)], dp[p] + ((j != i+1) ? 1 : 0));
break;
}
}
}
}
}
return *max_element(dp.begin(), dp.end());
}
int solve(const string &S) {
const int N = S.size();
// pos, height, last (+: 0, -: 1)
int dp[2][5010][2];
memset(dp, ~0, sizeof(dp));
dp[0][0][1] = 0;
for (int i = 0; i < N; ++i) {
auto crt = dp[i & 1];
auto nxt = dp[(i + 1) & 1];
const int lim = min(i, N - i);
for (int x = 0; x <= lim + 1; ++x) for (int s = 0; s < 2; ++s) nxt[x][s] = -1;
for (int x = 0; x <= lim; ++x) for (int s = 0; s < 2; ++s) if (~crt[x][s]) {
// discard
if (x == 0) {
chmax(nxt[x][s], crt[x][s]);
}
// +
if (S[i] == '?' || S[i] == '>') {
chmax(nxt[x + 1][0], crt[x][s] + 1);
}
// -
if (S[i] == '?' || S[i] == '<') {
if (s == 0) {
// yama: choose [-1, +1]
for (int y = max(x - 1, 0); y <= x + 1; ++y) {
chmax(nxt[y][1], crt[x][s]);
}
} else {
if (x) {
chmax(nxt[x - 1][1], crt[x][s] + 1);
}
}
}
}
}
int ans = -1;
for (int s = 0; s < 2; ++s) {
chmax(ans, dp[N & 1][0][s]);
}
return ans;
}
void exper() {
for (int n = 1; n <= 10; ++n) {
for (int p = 0; p < 1 << n; ++p) {
string s(n, '?');
for (int i = 0; i < n; ++i) s[i] = "<>"[p >> i & 1];
const int brt = brute(s);
assert(brt <= n - 1);
if (brt == n - 1) {
cerr << s << " " << brt << endl;
}
cout << s << " " << brt << endl;
vector<int> dp(n + 1, 0);
dp[0] = 0;
for (int i = 0; i < n; ++i) {
chmax(dp[i + 1], dp[i]);
for (int j = i + 1; j <= n; ++j) {
/*
const int half = (j - i) / 2;
if (s.substr(i, half) == string(half, '>') &&
s.substr(j - half, half) == string(half, '<')) {
chmax(dp[j], dp[i] + (j - i - 1));
}
*/
int yama = 0;
int can = 1 << 0;
for (int k = i; k < j; ++k) {
if (i < k && s[k - 1] == '>' && s[k] == '<') {
// choose [-1, +1]
++yama;
can = can >> 1 | can | can << 1;
}
can = (s[k] == '>') ? (can << 1) : (can >> 1);
}
if (can >> 0 & 1) {
chmax(dp[j], dp[i] + (j - i - yama));
}
}
}
if (brt != dp[n]) {
cerr << s << " " << brt << " " << dp << endl;
}
assert(brt == dp[n]);
}
cerr << "DONE n = " << n << endl;
}
}
int main() {
// exper(); return 0;
char buf[5010];
for (int numCases; ~scanf("%d", &numCases); ) { for (int caseId = 1; caseId <= numCases; ++caseId) {
scanf("%s", buf);
const int brt = brute(buf);
printf("%d\n", brt);
}
#ifndef LOCAL
break;
#endif
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 17ms
memory: 12028kb
input:
10 ?>? >?< ??<? ?><?< ?????? >?<?<>?<?< ?><???><>< ??>>><><?? <>>?>>?>?> <?<>>??<?>
output:
2 2 3 4 5 8 7 8 5 6
result:
ok 10 numbers
Test #2:
score: -100
Time Limit Exceeded
input:
100000 >?<?<>?<?< ?><???><>< ??>>><><?? <>>?>>?>?> <?<>>??<?> >><>><<<<< >?>?>?<<>> ?><?<<?<>< ???><>?>?> <??>?<<><? ??>><?<>>> <><><?<>>? ?>>?>???>< ?<?><?<<>? >>><?<??>< ><><<>?>?< >?><>><<<? >??>?><?<> ?????<><?> <><<?<<>?< ><?>>?>?>? ?><><<<>>? ?<>?<>?<<< <><<<<<>>> ?>?>?><<>> <>?<>><>?< <<<?<>>...