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poj2752 扩展kmp

2016-05-07 22:43 393 查看
/**********************jibancanyang**************************
*Author*        :jibancanyang
*Created Time*  : 六  5/ 7 21:17:06 2016
*File Name*     : .cpp
**Problem**:扩展kmp
**Analyse**:

**Code**:
***********************1599664856@qq.com**********************/

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <stack>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
typedef unsigned long long ull;
vector<int> vi;
#define pr(x) cout << #x << ": " << x << "  "
#define pl(x) cout << #x << ": " << x << endl;
#define pri(a) printf("%d\n",(a));
#define xx first
#define yy second
#define sa(n) scanf("%d", &(n))
#define sal(n) scanf("%lld", &(n))
#define sai(n) scanf("%I64d", &(n))
#define vep(c) for(decltype((c).begin() ) it = (c).begin(); it != (c).end(); it++)
const int mod = int(1e9) + 7, INF = 0x3fffffff;
const int maxn = 4e5 + 13;
char t[maxn], s[maxn];
int nexts[maxn], extend[maxn], slen, tlen;

//计算next数组,保存到next参数中。
void getextendnexts(void)
{
tlen = slen = strlen(s);
for (int i = 1, j = -1, a, p; i < tlen; i++, j--)
if (j < 0 || i + nexts[i - a] >= p) {
if (j < 0)  j = 0, p = i;
while (p < tlen && t[j] == t[p]) j++, p++;
nexts[i] = j, a = i;
}
else nexts[i] = nexts[i - a];
}

void getextend (void)
{
getextendnexts();  //计算next数组。mx是表示最大长度的常数。
for (int i = 0, j = -1, a, p; i < slen; i++, j--)
if (j < 0 || i + nexts[i - a] >= p) {
if (j < 0)  j = 0, p = i;
while (p < slen && j < tlen && s[p] == t[j]) j++, p++;
extend[i] = j, a = i;
}
else extend[i] = nexts[i - a];
}

int main(void)
{
#ifdef LOCAL
//    freopen("/Users/zhaoyang/in.txt", "r", stdin);
//freopen("/Users/zhaoyang/out.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);
while (~scanf("%s", s)) {
memcpy(t, s, sizeof(s));
getextend();
for (int i = slen - 1; i >= 0; i--) {
if (extend[i] >= slen - i) {
printf("%d ", slen - i);
}
}
printf("\n");
}
return 0;
}
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