cf round 658 C2 贪心+乱搞 46ms

#include<stdio.h>

char s[100005];
char s1[100005];
char s3[100005];
int st[500005], tp;

int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        int n;
        scanf("%d",&n);
        scanf("%s",s);
        scanf("%s",s1);
        for(int i = 0; i < n; i++) s[i] -= '0',s1[i] -= '0';
        s[n] = s1[n] = s3[n] = 0;
        int cnt = 0;
        do
        {
            tp = 0;
            st[++tp] = n-cnt;
            for(int i = 0; i < n; i++) s3[i] = ((i<n-cnt)?(s[i]^1):s[i]);
            for(int i = 0; i < (n-cnt)/2; i++) s3[i] ^= s3[n-cnt-i-1] ^= s3[i] ^= s3[n-cnt-i-1];
            for(int i = 0; i < n; i++)
            {
                if(s3[i]^s1[i])
                {
                    int j = i+1;
                    while(s3[j]^s1[j] && s3[j] == s3[i]) j++;
                    st[++tp] = j;
                    if(!i) {i=j-1;continue;}
                    st[++tp] = j-i;
                    st[++tp] = j;
                    i = j-1;
                }
            }
            cnt = (cnt * cnt + cnt+1) % n;
        }while(tp > 2*n);
        printf("%d",tp);
        for(int i = 1; i <= tp; i++) printf(" %d%s",st[i],i==tp?"
":"");
        if(!tp) puts("");
    }
    return 0;
}