bzoj2251: [2010Beijing Wc]外星联络

orz JT真是太神辣

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>

using namespace std;

void setIO(const string& s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
template<typename Q> Q read(Q& x) {
    static char c, f;
    for(f = 0; c = getchar(), !isdigit(c); ) if(c == '-') f = 1;
    for(x = 0; isdigit(c); c = getchar()) x = x * 10 + c - '0';
    if(f) x = -x;
    return x;
}
template<typename Q> Q read() {
    static Q x; read(x); return x;
}


const int N = 3000 + 10;

char s[N];
int sa[N], n;
void build_sa(int m) {
    static int t1[N * 2], t2[N * 2], c[N];
    int *x = t1, *y = t2;
    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 = 0; i < n; i++) sa[--c[x[i]]] = i;
    
    for(int k = 1; k < n; k <<= 1) {
        int p = 0;
        for(int i = n - 1; i >= n - k; i--) y[p++] = i;
        for(int i = 0; i < n; i++) if(sa[i] >= k) y[p++] = sa[i]-k;
        for(int i = 0; i < m; i++) c[i] = 0;
        for(int i = 0; i < n; i++) c[x[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];
        
        p = 1, swap(x, y), x[sa[0]] = 0;
        for(int i = 1; i < n; i++) {
            x[sa[i]] = (y[sa[i]] == y[sa[i-1]] && y[sa[i]+k] == y[sa[i-1]+k]) ? p - 1 : p++;
        }
        if(p >= n) break;
        m = p;
    }
}

int rank[N], height[N];

void build_height() {
    for(int i = 0; i < n; i++) rank[sa[i]] = i;
    for(int k = 0, i = 0; i < n; i++) {
        if(k) k--;
        if(!rank[i]) continue;
        int j = sa[rank[i]-1];
        while(s[i+k] == s[j+k]) k++;
        height[rank[i]] = k;
    }
}

int main() {
#ifdef DEBUG
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#endif
    
    
    scanf("%d%s", &n, s);
    build_sa(256);
    build_height();
    
    for(int R, L = 1; L < n; L++) {
        for(int h = height[L-1] + 1; h <= height[L]; h++) {
            for(R = L + 1; height[R] >= h; R++);
            printf("%d\n", R - L + 1);
        }
    }
    
    return 0;
}

 

暴力也兹辞

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>

using namespace std;

void setIO(const string& s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
template<typename Q> Q read(Q& x) {
    static char c, f;
    for(f = 0; c = getchar(), !isdigit(c); ) if(c == '-') f = 1;
    for(x = 0; isdigit(c); c = getchar()) x = x * 10 + c - '0';
    if(f) x = -x;
    return x;
}
template<typename Q> Q read() {
    static Q x; read(x); return x;
}

const int N = 3000 + 10;

struct Trie {
    const static int maxnode = N * N;
    int ch[maxnode][2];
    int val[maxnode];
    int sz;
    
    int newnode() {
        ch[sz][0] = ch[sz][1] = 0;
        val[sz] = 0;
        return sz++;
    }
    
    void init() {
        sz = 0;
        newnode();
    }
    
    void insert(const char *s) {
        int u = 0, n = strlen(s);
        for(int i = 0; i < n; i++) {
            int c = s[i] - '0';
            if(!ch[u][c]) ch[u][c] = newnode();
            u = ch[u][c];
            val[u]++;
        }
    }
    
    void dfs(int u) {
        if(val[u] > 1) {
            printf("%d\n", val[u]);
        }
        if(ch[u][0]) dfs(ch[u][0]);
        if(ch[u][1]) dfs(ch[u][1]);
    }
}trie;

int main() {
#ifdef DEBUG
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#endif
    
    trie.init();
    int n;
    char s[N];
    scanf("%d%s", &n, s);
    for(int i = 0; i < n; i++) {
        trie.insert(s+i);
    }
    trie.dfs(0);
    
    return 0;
}