Ultraviolet A 11855-buzzwords (suffix array)

Link to the question: Ultraviolet A 11855-buzzwords

For a given string, the number of duplicates with a length greater than 1 (each length is counted as the maximum number of duplicates) is output in ascending order.

Solution: suffix array: process the suffix array, enumerate the length of the substring, and segment it by length.

#include <cstdio>#include <cstring>#include <vector>#include <algorithm>using namespace std;const int maxn = 1005;struct Suffix_Arr {    int n, s[maxn];    int SA[maxn], rank[maxn], height[maxn];    int tmp_one[maxn], tmp_two[maxn], c[maxn];    vector<int> vec;    void init (char* str);    void build_arr(int m);    void get_fail();    void solve();    void check(int k);}AC;char str[maxn];int main () {    while (gets(str) && strcmp(str, "")) {        AC.init(str);        AC.build_arr(27);        AC.get_fail();        AC.solve();        printf("\n");    }    return 0;}void Suffix_Arr::check(int k) {    int c = 0, ret = 0;    for (int i = 0; i <= n; i++) {        if (height[i] < k) {            ret = max(ret, c);            c = 1;        } else            c++;    }    if (ret > 1)        vec.push_back(ret);}void Suffix_Arr::solve() {    /*    for (int i = 0; i < n; i++)        printf("%d ", SA[i]);    printf("\n");    for (int i = 0; i < n; i++)        printf("%d ", height[i]);    printf("\n");    */    for (int i = 1; i <= n; i++)        check(i);    for (int i = 0; i < vec.size(); i++)        printf("%d\n", vec[i]);}void Suffix_Arr::init(char* str) {    n = 0;    vec.clear();    memset(height, 0, sizeof(height));    int len = strlen(str);    for (int i = 0; i < len; i++) {        if (str[i] != ‘ ‘)            s[n++] = str[i] - ‘A‘ + 1;    }    s[n++] = 0;    /*    for (int i = 0; i < n; i++)        printf("%c", s[i] ? ‘A‘ + s[i] - 1 : ‘!‘);    printf("\n");    */}void Suffix_Arr::get_fail() {    for (int i = 0; i < n; i++)        rank[SA[i]] = i;    int mv = 0;    for (int i = 0; i < n - 1; i++) {        if (mv) mv--;        int j = SA[rank[i] - 1];        while (s[i+mv] == s[j+mv])            mv++;        height[rank[i]] = mv;    }}void Suffix_Arr::build_arr (int m) {    int *x = tmp_one, *y = tmp_two;    for (int i = 0; i < m; i++) c[i] = 0;    for (int i = 0; i < n; i++) c[x[i] = s[i]]++;    for (int i = 1; i < m; i++) c[i] += c[i-1];    for (int i = n - 1; i >= 0; i--) SA[--c[x[i]]] = i;    for (int k = 1; k <= n; k <<= 1) {        int mv = 0;        for (int i = n - k; i < n; i++) y[mv++] = i;        for (int i = 0; i < n; i++) if (SA[i] >= k)            y[mv++] = SA[i] - k;        for (int i = 0; i < m; i++) c[i] = 0;        for (int i = 0; i < n; i++) c[x[y[i]]]++;        for (int i = 1; i < m; i++) c[i] += c[i-1];        for (int i = n - 1; i >= 0; i--) SA[--c[x[y[i]]]] = y[i];        swap(x, y);        mv = 1;        x[SA[0]] = 0;        for (int i = 1; i < n; i++)            x[SA[i]]  = (y[SA[i-1]] == y[SA[i]] && y[SA[i-1] + k] == y[SA[i] + k] ? mv - 1 : mv++);        if (mv >= n)            break;        m = mv;    }}

Ultraviolet A 11855-buzzwords (suffix array)