SDE Path

Number of Provinces

Medium

Number of Provinces

Given a matrix representing direct connections, find the number of connected components (provinces).

Input format

The first line contains N. The next N lines contain an N×N symmetric adjacency matrix (0 or 1, diagonal is 1).

Output format

Print the number of connected components.

Constraints

  • Values fit in a 64-bit signed integer
  • Trailing whitespace and a trailing newline are ignored by the judge

Read from stdin, write to stdout. Sample cases below show the exact format.

Sample cases

Example 1
Input
2
1 1
1 1
Expected output
1
Example 2
Input
12
1 0 0 1 0 0 0 0 0 0 0 0
0 1 0 1 0 1 1 1 0 1 1 0
0 0 1 1 1 1 1 0 1 1 1 0
1 1 1 1 1 1 1 0 1 0 0 0
0 0 1 1 1 1 1 0 1 1 1 1
0 1 1 1 1 1 0 1 0 1 1 0
0 1 1 1 1 0 1 0 1 0 0 1
0 1 0 0 0 1 0 1 0 0 0 0
0 0 1 1 1 0 1 0 1 1 0 1
0 1 1 0 1 1 0 0 1 1 0 0
0 1 1 0 1 1 0 0 0 0 1 1
0 0 0 0 1 0 1 0 1 0 1 1
Expected output
1