n = int(input()) arr = [[0 for i in range(n+1)] for j in range(n+1)] y=x=0 num=1 for i in range(1,n+1): for j in range(i): arr[y][x]=num num+=1 if i % 2 == 1 : y+=1;x-=1 else : y-=1;x+=1 if i % 2 == 1 : x+=1 else : y+=1 if i%2==0 : y+=1;x-=1 else: y-=1;x+=1 for i in range(n-1,0,-1): for j in range(i): arr[y][x]=num num+=1 if i % 2 == 1 : y+=1;x-=1 else : y-=1;x+=1 if i % 2 == 1 : y-=1;x+=2 else ..