#include<cstdio> #include<vector> using namespace std; using vi=vector<int>; using vvi=vector<vector<int> >; struct count_t { int win, lose; }; int count(vvi& s) { int n=s.size(); vi c(n); int rank=0; vi b(n); for(int y=0;y<n;y++) { for(int x=0;x<n;x++) { if(s[y][x]=='o') c[y]++; } b[c[y]]++; } for(int i=n-1;i>=0;i--) { if(b[i]) rank++; if(c[0]==i) return rank; } return 999; } int min_u(int& m, int v) { if(m>v) { m=v; return 1; } return 0; } void vvi_dump(const vvi& s) { unsigned x, y; for(y=0;y<s.size();y++) { for(x=0;x<s[y].size();x++) printf("%c", s[y][x]); printf("\n"); } printf("\n"); } int solve(vvi& w) { int n=w.size(); int ret=n; for(int y=0;y<n;y++) { for(int x=y+1;x<n;x++) { if(w[y][x]!='-') continue; w[y][x]='o', w[x][y]='x'; min_u(ret, solve(w)); w[y][x]='x', w[x][y]='o'; min_u(ret, solve(w)); w[y][x]='-', w[x][y]='-'; return ret; } } // vvi_dump(w); return count(w); } int main(void) { vvi s; vector<count_t> c; int n; int x, y; while(scanf("%d", &n)==1) { c.resize(n); s.resize(n); for(y=0;y<n;y++) { char buf[6+2]; s[y].resize(n); scanf("%s", buf); for(x=0;x<n;x++) { s[y][x]=buf[x]; } } /* for(x=0;x<n;x++) { if(s[0][x]=='-') { s[0][x]='o'; s[x][0]='x'; } } */ printf("%d\n", solve(s)); } return 0; }