Bark to Unlock CodeForces

判自身，判相接

#include <iostream>#include <cstdio>#include <cstdlib>#include <cstring>#include <string>#include <cmath>#include <set>#include <map>#include <stack>#include <queue>#include <ctype.h>#include <vector>#include <algorithm>#include <sstream>#define PI acos(-1.0)#define in freopen("in.txt", "r", stdin)#define out freopen("out.txt", "w", stdout)using namespace std;typedef long long ll;const int maxn = 1000 + 7, INF = 0x7f7f7f7f, mod = 1e9 + 7;int n;char s[4], t[6];int main() {    scanf("%s", s);    scanf("%d", &n);    int f1 = 0, f2 = 0;    for(int i = 0; i < n; ++i) {        scanf("%s", t);        if(t[0] == s[0] && t[1] == s[1]) { f1 = f2 = 1; }        if(t[0] == s[1]) f1 = 1;        if(t[1] == s[0]) f2 = 1;    }    if(f1 + f2 == 2) puts("YES");    else puts("NO");    return 0;}