UV 10526, uva10526

UV 10526, uva10526
Ultraviolet A 10526-Intellectual Property

Question Link

Question: Given two questions, it is required to find all the positions and lengths of the first text copied by the second text, and output the first k, sorted by length from large to small, the length is the same from small to large.

Idea: suffix array, concatenate two texts, record the splicing position as tdp, So If sa [I] <tdp is the beginning of the text, if sa [I]> = tdp is the beginning of the subsequent text, concatenate the height array, and use the properties of the array to scan the array from the beginning to the end, save the maximum values of all locations, scan the locations, and record the answers.

Code:

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int MAXLEN = 200005;const int INF = 0x3f3f3f3f;char str[55555];int k, tdp, an, v[MAXLEN];struct Ans {    int len, pos;    Ans() {}    Ans(int len, int pos) {this->len = len;this->pos = pos;    }} ans[MAXLEN];bool cmp(Ans a, Ans b) {    if (a.len == b.len) return a.pos < b.pos;    return a.len > b.len;}struct Suffix {    int s[MAXLEN];    int sa[MAXLEN], t[MAXLEN], t2[MAXLEN], c[MAXLEN], n;    int rank[MAXLEN], height[MAXLEN];    void build_sa(int m) {n++;int i, *x = t, *y = t2;for (i = 0; i < m; i++) c[i] = 0;for (i = 0; i < n; i++) c[x[i] = s[i]]++;for (i = 1; i < m; i++) c[i] += c[i - 1];for (i = n - 1; i >= 0; i--) sa[--c[x[i]]] = i;for (int k = 1; k <= n; k <<= 1) {    int p = 0;    for (i = n - k; i < n; i++) y[p++] = i;    for (i = 0; i < n; i++) if (sa[i] >= k) y[p++] = sa[i] - k;    for (i = 0; i < m; i++) c[i] = 0;    for (i = 0; i < n; i++) c[x[y[i]]]++;    for (i = 0; i < m; i++) c[i] += c[i - 1];    for (i = n - 1; i >= 0; i--) sa[--c[x[y[i]]]] = y[i];    swap(x, y);    p = 1; x[sa[0]] = 0;    for (i = 1; i < n; i++)x[sa[i]] = (y[sa[i - 1]] == y[sa[i]] && y[sa[i - 1] + k] == y[sa[i] + k]) ? p - 1 : p++;    if (p >= n) break;    m = p;}n--;    }    void getHeight() {int i, j, k = 0;for (i = 1; i <= n; i++) rank[sa[i]] = i;for (i = 0; i < n; i++) {    if (k) k--;    int j = sa[rank[i] - 1];    while (s[i + k] == s[j + k]) k++;    height[rank[i]] = k;}    }    void init() {tdp = 0; n = 0; an = 0;gets(str);while (gets(str)) {    if (strcmp(str, "END TDP CODEBASE") == 0) break;    int len = strlen(str);    str[len] = '\n';    for (int i = 0; i <= len; i++)s[n++] = str[i];}tdp = n;gets(str);while (gets(str)) {    if (strcmp(str, "END JCN CODEBASE") == 0) break;    int len = strlen(str);    str[len] = '\n';    for (int i = 0; i <= len; i++)s[n++] = str[i];}s[n] = 0;    }    void solve() {init();build_sa(256);getHeight();memset(v, 0, sizeof(v));int Min = -1;for (int i = 1; i <= n; i++) {    if (sa[i] < tdp) Min = INF;    else {if (Min == -1) continue;Min = min(height[i], Min);v[sa[i] - tdp] = max(Min, v[sa[i] - tdp]);    }}Min = -1;for (int i = n; i >= 1; i--) {    if (sa[i] < tdp) Min = INF;    else {if (Min == -1) continue;Min = min(height[i + 1], Min);v[sa[i] - tdp] = max(Min, v[sa[i] - tdp]);    }}int r = -1;for (int i = 0; i < n - tdp; i++) {    if (i + v[i] <= r) continue;    if (v[i] == 0) continue;    ans[an++] = Ans(v[i], i);    r = i + v[i];}sort(ans, ans + an, cmp);for (int i = 0; i < min(an, k); i++) {    printf("INFRINGING SEGMENT %d LENGTH %d POSITION %d\n", i + 1, ans[i].len, ans[i].pos);    for (int j = ans[i].pos + tdp; j < ans[i].pos + tdp + ans[i].len; j++)printf("%c", s[j]);    printf("\n");}    }} gao;int main() {    int bo = 0;    int cas = 0;    while (~scanf("%d%*c", &k) && k) {if (bo) printf("\n");else bo = 1;printf("CASE %d\n", ++cas);gao.solve();    }    return 0;}