Ultraviolet A 10526-Intellectual Property (suffix array)

Link to the question: Ultraviolet A 10526-Intellectual Property

Given two texts, I would like to explain where the following text copied the previous one and output n plagiarism locations (if less than N copies are all output ), output is prioritized by length, with the same length at the top.
Note: space indicates that the carriage return is a single character. A segment of characters can only be a part of the copy. For example, if the upper part is NSB * Sb, the answer is NSB.

Solution: connect the two texts, separate them with unused characters in the middle, and then process the suffix array. According to the nature of the height array, find out which locations do not match the length of 0 (note that the matching position is the maximum length of the next section and the previous section), and the subscript of the Data splitter can distinguish between the front and back texts. Then, overwrite the sorting output.

#include <cstdio>#include <cstring>#include <vector>#include <algorithm>using namespace std;const int maxn = 200005;struct state {    int pos, len;    state (int pos = 0, int len = 0) {        this->pos = pos;        this->len = len;    }};struct Suffix_Arr {    int n, s[maxn];    int SA[maxn], rank[maxn], height[maxn];    int tmp_one[maxn], tmp_two[maxn], c[maxn];    void init();    void add(char* str);    void build_arr(int m);    void get_height();    void solve (int p);}AC;inline bool sort_len (const state& a, const state& b) {    if (a.len != b.len)        return a.len > b.len;    return a.pos < b.pos;}inline bool sort_pos (const state& a, const state& b) {    if (a.pos != b.pos)        return a.pos < b.pos;    return a.len > b.len;}int N, tick;char str[maxn];void init () {    AC.init();    gets(str);    while (gets(str) && strcmp(str, "END TDP CODEBASE"))        AC.add(str);    AC.s[AC.n++] = 260;    tick = AC.n;    gets(str);    while (gets(str) && strcmp(str, "END JCN CODEBASE"))        AC.add(str);    AC.s[AC.n++] = 0;    AC.build_arr(261);    AC.get_height();}int main () {    int cas = 0;    while (~scanf("%d%*c", &N) && N) {        init();        if (cas)            printf("\n");        printf("CASE %d\n", ++cas);        AC.solve(tick);    }    return 0;}void Suffix_Arr::solve(int p) {    int k = 0;    memset(c, 0, sizeof(c));    for (int i = 0; i < n; i++) {        if (SA[i] < p)            k = height[i+1];        else {            k = min(height[i], k);            c[i] = max(c[i], k);        }    }    k = 0;    for (int i = n - 1; i >= 0; i--) {        if (SA[i] < p) {            k = height[i];        } else {            c[i] = max(c[i], k);            k = min(height[i], k);        }    }    vector<state> vec, ans;    for (int i = 0; i < n; i++) {        if (c[i] >= 1)            vec.push_back(state(SA[i], c[i]));    }    sort(vec.begin(), vec.end(), sort_pos);    int mv = -1;    for (int i = 0; i < vec.size(); i++) {        if (vec[i].pos + vec[i].len <= mv)            continue;        ans.push_back(vec[i]);        mv = vec[i].pos + vec[i].len;    }    sort(ans.begin(), ans.end(), sort_len);    for (int i = 0; i < N && i < ans.size(); i++) {        printf("INFRINGING SEGMENT %d LENGTH %d POSITION %d\n", i+1, ans[i].len, ans[i].pos - p);         for (int j = 0; j < ans[i].len; j++)            printf("%c", s[ans[i].pos + j]);        printf("\n");    }}void Suffix_Arr::init() {    n = 0;    memset(s, 0, sizeof(s));    memset(height, 0, sizeof(height));}void Suffix_Arr::add (char *str) {    int len = strlen(str);    for (int i = 0; i < len; i++)        s[n++] = str[i];    s[n++] = ‘\n‘;}void Suffix_Arr::get_height () {    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 10526-Intellectual Property (suffix array)