翻硬币

#include<iostream>
#include<cstring>

using namespace std;

const int INF = 1e6;
const int N = 110;

char g[N], gg[N];
int dx[] = {0, -1};
int t;

void turn(int x) {
    for(int i = 0; i < 2; i ++) {
        int a = dx[i] + x;
        if(a >= 0 && a < t / 2) {  // 范围一开始没划好
            if(g[a] == '*') g[a] = 'o';
            else g[a] = '*';
        }
    }
}

int work() {
    int ans = INF;
    for(int k = 0; k < 2; k ++) {
        char backup[N];
        int res = 0;
        memcpy(backup, g, t / 2);
        for(int i = 0; i < 2; i ++) 
            if(k >> i && 1 ) {
                res ++;
                turn(i);
            }

        for(int i = 0; i < t / 2 - 1; i ++) 
            if(g[i] != g[i + (t / 2)]) {
                res ++;
                turn (i + 1);
            }

        if(g[t / 2 - 1] == g[t - 1]) ans = min(ans, res);
        memcpy(g, backup, t / 2);
    }
    return ans;
}

int main() {
    char x;
    while(cin >> x) g[t ++] = x;
    cout << work() << endl;
    return 0;
}