Codeforces Round #516 (Div. 1, by Moscow Team Olympiad) E

#include<bits/stdc++.h>
#define N 1006
using namespace std;
int n,a[N],last;
char ans[N][N];
signed main () {
    scanf("%d",&n);
    for (int i=1;i<=n;i++) {
     scanf("%d",a+i); 
     if (a[i]!=i) last=i; }
    if (last) {
        char x=‘/‘, y=‘\\‘;
        for(int i=n;i;--i){
            int p=0;
            if(x==‘/‘){for(int j=1;j<last;++j) if(a[j]!=j){ p=j; break;} }
            else for(int j=n;j>last;--j) if(a[j]!=j){ p=j; break;}
            if(!p) break;
            ans[i][p]=ans[i][last]=ans[i][a[p]]=x;
            a[last]=a[a[p]], a[a[p]]=a[p], last=p;
            swap(x,y);
            cerr<<last<<endl;
        }
    }
    printf("%d\n",n-(!!last));
    for(int i=1; i<=n; ++i, puts("")) for(int j=1; j<=n; ++j) putchar(ans[i][j]?ans[i][j]:‘.‘);
}