高層タワー [MISSION LEVEL: B]

很久之前就看见过这个网站，今天突然想做一下试试hh

题面

方法

用的kmp。。。搞了好半天

#include<iostream>
#include<cstring>

using namespace std;

const int N = 10010;

char res[2][N];
int cnt, n;
int ne[N];

int main(){
    cin >> n;
    
    for(int i = 0; i < n; i ++){
        int cur = i & 1, bef = cur ^ 1;
        cin >> res[cur];
        
        if(i){
            int a = strlen(res[cur]);
            int b = strlen(res[bef]);
            
            for(int i = 0, j = ne[0] = -1; i <= a; ne[++ i] = ++ j)
                while(~j && res[cur][i] != res[cur][j]) j = ne[j];
                
            int p = 0, q = 0;
            while(p < b){
                while(~q && res[bef][p] != res[cur][q]) q = ne[q];
                ++ p, ++ q;
                if(q == a && p < b) q = ne[q];
            }
            
            for(int j = b; q < a; ++ q, ++ j) res[bef][j] = res[cur][q];
            memcpy(res[cur], res[bef], sizeof res[bef]);
        }
    }
    cout << res[(n - 1) & 1 ^ 1];
    return 0;
}