#include<iostream>#include<cstdio>#include<cstring>using namespace std;int map1[230][230], ans, n, m;int dir[4][2] = {0,1,0,-1,1,0,-1,0};int gauss(){    int i,j,k,t;    for(i=0,j=0; i<n && j<n; i++,j++)    {        k=i;        while(!map1[k][j] && k<n)            k++;        if(k==n)        {            i--;            continue;        }        if(k!=i)            for(t = j; t <= n; t++)                swap(map1[i][t],map1[k][t]);        for(k=i+1; k < n; k++)            if(map1[k][j])                for(t=j; t<=n; t++)                    map1[k][t]^=map1[i][t];    }    k=i;    for(i=k; i<n; i++)    {        if(map1[i][n])            return -1;        //while(1);    }    for(i=k-1,t=0; i >= 0; i--)    {        for(j=i+1; j<n; j++)            map1[i][n]^=(map1[i][j]&&map1[j][n]);        if(map1[i][n]) t++;    }    return t;}int main(){    int cas, i, j, ans;    char c;    scanf("%d", &cas);    while (cas--)    {        scanf("%d", &m);        memset(map1, 0, sizeof (map1));        n = m*m;        for (i = 0; getchar(), i < m; i++)            for (j = 0; j < m; j++)            {                c = getchar();                if (c == ‘w‘)                    map1[i * m+j][n] = 1;                else                    map1[i * m+j][n] = 0;            }        for (i = 0; i < m; i++)            for (j = 0; j < m; j++)            {                map1[i*m+j][i*m+j]=1;                for(int k=0; k<4; k++)                {                    int dx=i+dir[k][0],dy=j+dir[k][1];                    if(dx>=0 && dx<m && dy>=0 && dy<m)                        map1[dx*m+dy][i*m+j]=1;                }            }        ans=gauss();        if(ans==-1)            printf("inf\n");        else            printf("%d\n",ans);    }    return 0;}/*54wwwwwwwwwwwwwwww5result 4 but compute result is 10 . this is because free radical is not enum.*/