oj.uz

Submission #134930

# Submission time Handle Problem Language Result Execution time Memory
134930 2019-07-23T12:26:13 Z wilwxk Palindromes (APIO14_palindrome) C++14
23 / 100
 1000 ms 7932 KB 
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

const int MAXN=3e5+5;
const ll MOD=1e9+9;
const ll P=257;
char c[MAXN];
ll h[MAXN], rh[MAXN];
ll pot[MAXN];
int n;
ll respf=0;

ll ghash(int ini, int fim) {
	ll val=0;
	if(ini<=fim) {
		if(ini!=0) val=h[ini-1];
		val*=pot[fim-ini+1]; val%=MOD;
		val=h[fim]-val;
		while(val<0) val+=MOD;
	}
	else {
		if(ini!=n-1) val=rh[ini+1];
		val*=pot[ini-fim+1]; val%=MOD;
		val=rh[fim]-val;
		while(val<0) val+=MOD;
	}
	return val;
}

int testa(int k) {
	int resp=0;
	// printf("testing %d\n", k);
	unordered_map<ll, int> mp;
	for(int i=k-1; i<n; i++) {
		int ind=i-k+1;
		ll val=ghash(ind, i);
		// printf("  %d: %lld %lld\n", i, val, ghash(i, ind));
		if(val==ghash(i, ind)) {
			mp[val]++;
			resp=max(resp, mp[val]);
		}
	}
	return resp;
}

void precalc() {
	pot[0]=1;
	for(int i=1; i<=n; i++) pot[i]=(pot[i-1]*P)%MOD;
	for(int i=0; i<n; i++) {
		if(i!=0) h[i]=(h[i-1]*P)%MOD;
		h[i]+=(c[i]-'a'); h[i]%=MOD;
	}
	for(int i=n-1; i>=0; i--) {
		if(i!=n-1) rh[i]=(rh[i+1]*P)%MOD;
		rh[i]+=(c[i]-'a'); rh[i]%=MOD;
	}
}

int main() {
	scanf(" %s", c); n=strlen(c);
	precalc();

	for(int i=1; i<=n; i++) {
		ll val=testa(i);
		val*=i;
		respf=max(respf, val);
	}

	printf("%lld\n", respf);
}

Compilation message

palindrome.cpp: In function 'int main()':
palindrome.cpp:61:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf(" %s", c); n=strlen(c);
  ~~~~~^~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 380 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 2 ms 376 KB Output is correct
13 Correct 2 ms 376 KB Output is correct
14 Correct 2 ms 420 KB Output is correct
15 Correct 2 ms 376 KB Output is correct
16 Correct 2 ms 376 KB Output is correct
17 Correct 2 ms 376 KB Output is correct
18 Correct 2 ms 376 KB Output is correct
19 Correct 2 ms 376 KB Output is correct
20 Correct 2 ms 376 KB Output is correct
21 Correct 2 ms 376 KB Output is correct
22 Correct 2 ms 504 KB Output is correct
23 Correct 2 ms 376 KB Output is correct
24 Correct 3 ms 376 KB Output is correct
25 Correct 2 ms 376 KB Output is correct
26 Correct 2 ms 376 KB Output is correct
27 Correct 3 ms 404 KB Output is correct
28 Correct 2 ms 376 KB Output is correct
29 Correct 2 ms 376 KB Output is correct
30 Correct 2 ms 376 KB Output is correct
31 Correct 2 ms 380 KB Output is correct
32 Correct 2 ms 376 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 22 ms 376 KB Output is correct
2 Correct 19 ms 376 KB Output is correct
3 Correct 29 ms 376 KB Output is correct
4 Correct 16 ms 380 KB Output is correct
5 Correct 30 ms 376 KB Output is correct
6 Correct 29 ms 376 KB Output is correct
7 Correct 16 ms 376 KB Output is correct
8 Correct 22 ms 376 KB Output is correct
9 Correct 16 ms 376 KB Output is correct
10 Correct 16 ms 376 KB Output is correct
11 Correct 16 ms 376 KB Output is correct
12 Correct 16 ms 376 KB Output is correct

Subtask #3
0 / 24.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1079 ms 636 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 26.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1054 ms 2936 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1070 ms 7932 KB Time limit exceeded
2 Halted 0 ms 0 KB -