Problem

**hidden**## CCOMPS - Count Components

Given an undirected graph of N nodes (numbered from 1 to N) and M edges,

find the number of its connected components.

Given an undirected graph of N nodes (numbered from 1 to N) and M edges, find the number of its connected components.

### Input

The first line of input consists of two integers, N and M, the number of nodes and the number of edges respectively. (N ≤ 100000, M ≤ 200000)

The next M lines of input contain a pair of integers (x, y) representing anedge between nodes x and y. (1 ≤ x, y ≤ N)

### Output

To the first and only line of output, print a single integer: the number of connected components.

### Example

Input:5 2 1 2 3 4

Output:3

Added by: | gustav |

Date: | 2014-12-05 |

Time limit: | 1s |

Source limit: | 50000B |

Memory limit: | 1536MB |

Cluster: | Cube (Intel G860) |

Languages: | All except: ASM64 |

Resource: | classical problem |