难度：★

Code:

#include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;//Mystery_Sky//#define M 1000string s;int n, ans, flag, maxx, sum;int l[M], r[M];bool it[M];int main() {    scanf("%d", &n);    cin >> s;    for(int i = 0; i < n; i++) {        sum = 2;        int iter_1, iter_2;        char ster_1, ster_2;        iter_1 = i-1, iter_2 = i+2;        if(iter_1 < 0) iter_1 = n;        if(iter_2 >= n) iter_2 -= n;        ster_1 = s[i], ster_2 = s[i+1];        while(!ans) {//          printf("iter_1=%d\n", iter_1);            if(s[iter_1] == s[iter_1+1]) sum++;            else if(s[iter_1] == 'w') sum++;            else if(s[iter_1] == ster_1) sum++;            else if(ster_1 == 'w') {                sum++;                ster_1 = s[iter_1];            }            else break;            iter_1--;            if(iter_1 < 0) iter_1 = n-1;            if(iter_1 == iter_2-1) ans = n;        }        while(!ans) {            if(s[iter_2] == s[iter_2-1]) sum++;            else if(s[iter_2] == 'w') sum++;            else if(s[iter_2] == ster_2) sum++;            else if(ster_2 == 'w') {                sum++;                ster_2 = s[iter_2];            }            else break;            iter_2++;            if(iter_2 >= n) iter_2 = 0;        }        if(ans) break;        maxx = max(sum, maxx);    }    if(ans == n) printf("%d\n", ans);    else if(maxx > n) printf("%d\n", n);    else printf("%d\n", maxx);    return 0;    }