union-find

• Read in number of objects N from standard input.

  -・Repeat:
          – read in pair of integers from standard input
          – if they are not yet connected, connect them and print out pair

• resource: https://d3c33hcgiwev3.cloudfront.net/_b65e7611894ba175de27bd14793f894a_15UnionFind.pdf?Expires=1587945600&Signature=acCR6aDGXnA7luzAqFrIeDW6riwnUjsEuigduiwEkwFUkL9tvIH5k39Lo1bSy00AP0nC1QBlXexq6fqaGslGLbIbWBOc0jO99mi09BCFV6InmXXlPIIgk90DDf9Vk67O4tEs-jSRma7NSCCohSE6~WCb36UWOGVLQOIq7Amm5DY_&Key-Pair-Id=APKAJLTNE6QMUY6HBC5A
• EX: Monte Carlo Simulation `
• general example

public static void main(String[] args) {
  int N = StdIn.readInt();
  UF uf = new UF(N);

  while (!StdIn.isEmpty()) {
      int p = StdIn.readInt();
      int q = StdIn.readInt();

      if (!uf.connected(p, q)){
          uf.union(p, q);
          StdOut.println(p + " " + q);
          }
      }
  }