Submission #920129

#	Time	Username	Problem	Language	Result	Execution time	Memory
920129		TIN	Savez (COCI15_savez)	C++17	0 / 120	17 ms	1884 KiB

savez

#include <bits/stdc++.h>

using namespace std;

#define FNAME "test"

#define sz(s) (int) (s).size()

typedef long long ll;

const int base = 311;
const ll M = 1e9 + 3;
const int N = 505;
const int len = 2e5 + 5;

int n;
string s[N];
ll p[len], hashS[N][len];
ll dp[N];
ll ans = 0;

void Task() {
	ios_base::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	cout << fixed << setprecision(9);
	if (fopen(FNAME".inp","r")) {
		freopen(FNAME".inp","r",stdin);
		freopen(FNAME".out","w",stdout);
	}
}

void prepare() {
	p[0] = 1;
	for (int i = 1; i <= 2000000; i++) p[i] = (p[i - 1] * base) % M;
}

void update(int i, string s) {
	int lenS = sz(s);
	s = " " + s;
	hashS[i][0] = 0;
	for (int j = 1; j <= lenS; j++) hashS[i][j] = (hashS[i][j - 1] * base + s[j] + 1) % M;
}

ll getHash(int i, int l, int r) {
	return (hashS[i][r] - hashS[i][l - 1] * p[r - l + 1] + M * M) % M;
}

void Solve() {
	//Your Code
	prepare();
	cin >> n;
	dp[0] = 0;
	for (int i = 1; i <= n; i++) {
		cin >> s[i];
		update(i, s[i]);
	}
	for (int i = n; i >= 1; i--) {
		int best = 0;
		ll hashI = getHash(i, 1, sz(s[i]));
		ll hashHead, hashTail;
		for (int j = i + 1; j <= n; j++) {
			if (sz(s[j]) < sz(s[i])) continue;
			hashHead = getHash(j, 1, sz(s[i]));
			hashTail = getHash(j, sz(s[j]) - sz(s[i]) + 1, sz(s[j]));
			if (hashHead == hashI && hashI == hashTail) {
				if (dp[j] > dp[best]) {
					best = j;
				}
			}
		}
		dp[i] = dp[best] + 1;
		ans = max(ans, dp[i]);
	}
	cout << ans << '\n';
}

int main() {
	Task();
	Solve();
	cerr << "\nTime run: " << 1000*clock()/CLOCKS_PER_SEC << "ms";
	return 37^37;
}

Compilation message (stderr)

savez.cpp: In function 'void Task()':
savez.cpp:27:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |   freopen(FNAME".inp","r",stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
savez.cpp:28:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |   freopen(FNAME".out","w",stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
savez.cpp: In function 'void prepare()':
savez.cpp:34:52: warning: iteration 200005 invokes undefined behavior [-Waggressive-loop-optimizations]
   34 |  for (int i = 1; i <= 2000000; i++) p[i] = (p[i - 1] * base) % M;
      |                                             ~~~~~~~^
savez.cpp:34:20: note: within this loop
   34 |  for (int i = 1; i <= 2000000; i++) p[i] = (p[i - 1] * base) % M;
      |                  ~~^~~~~~~~~~

• Subtask 1: 0 / 12
• Subtask 2: 0 / 12
• Subtask 3: 0 / 12
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• Subtask 10: 0 / 12