POJ 3276 [Face The Right Way] 题解

#include <cstring>
const int maxn = 5500;
const int INF = 100243535;
int a[maxn], f[maxn], cnt[maxn];
int () {
    int n;
    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        char s[10];
        scanf("%s", s);
        a[i] = (s[0] == 'F' ? 0 : 1);
    }
    for (int k = 1; k <= n; k++) {
        memset(f, 0, sizeof(f));
        int turns = 0;
        for (int i = 0; i < n; i++) {
           
            if ((a[i] + turns) % 2 == 1) {
                if (i + k > n) {
                    cnt[k] = INF;
                    break;
                }
                f[i] = 1;
                cnt[k]++;
                turns++;
            }
            if (i - k + 1 >= 0) turns -= f[i - k + 1];
           
        }   
    }
    int ansK = 1;

    for (int k = 2; k <= n; k++) if (cnt[k] < cnt[ansK]) ansK = k;
   
    printf("%d %dn", ansK, cnt[ansK]);

}