[HIHO1152]Lucky Substrings（暴力，枚举）

题目链接：http://hihocoder.com/problemset/problem/1152

题意：给一个字符串，找所有的满足不同字符数为斐波那契数的子串。

暴力，枚举。

#include <bits/stdc++.h>
using namespace std;

const int maxn = 111;
const int maxm = 66;
int n;
int fib[maxm];
char s[maxn];
set<string> ret;
set<int> vis;

bool ok(int l, int r) {
    set<char> t;
    for(int i = l; i <= r; i++) t.insert(s[i]);
    if(vis.find(t.size()) != vis.end()) return 1;
    return 0;
}

int main() {
    // freopen("in", "r", stdin);
    char buf[maxn];
    memset(fib, 0, sizeof(fib));
    vis.clear();
    fib[0] = fib[1] = fib[2] = 1;
    fib[3] = 2;
    vis.insert(1);
    vis.insert(2);
    for(int i = 4; i < maxm; i++) {
        fib[i] = fib[i-1] + fib[i-2];
        vis.insert(fib[i]);
    }
    while(~scanf("%s", s)) {
        n = strlen(s);
        ret.clear();
        for(int l = 0; l < n; l++) {
            for(int r = l; r < n; r++) {
                if(ok(l, r)) {
                    memset(buf, 0, sizeof(buf));
                    for(int i = l; i <= r; i++) buf[i-l] = s[i];
                    ret.insert(buf);
                }
            }
        }
        for(set<string>::iterator it = ret.begin(); it != ret.end(); it++) {
            cout << *it << endl;
        }
    }
    return 0;
}