http://noi.openjudge.cn/ch0205/1388/
Lake Counting
描述
Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W') or dry land ('.'). Farmer John would like to figure out how many ponds have formed in his field. A pond is a connected set of squares with water in them, where a square is considered adjacent to all eight of its neighbors.

Given a diagram of Farmer John's field, determine how many ponds he has.
输入

• Line 1: Two space-separated integers: N and M
• Lines 2..N+1: M characters per line representing one row of Farmer John's field. Each character is either 'W' or '.'. The characters do not have spaces between them.
  输出
• Line 1: The number of ponds in Farmer John's field.

翻译
湖计算
描述
由于最近降雨，水聚集在农民John的田地的各个地方，用一个 N x M (1 <= N <= 100; 1 <= M <= 100)正方形的矩形表示。每个方块要么包含水 ('W') 要么是干燥的土地('.')。农民John想计算他的田地里形成多少个池塘。池塘是一组相互连接的正方形其中有水，其中一个正方形被视为与其所有八个相邻的正方形相邻。
输入
第一行:两个用空格分开的整数： N 和 M
第二行...N+1：每行M个字符表示农民John的田地。每个字符是'W'或'.'。字符之间没有空格。
输出
第一行：农民John的田地里的池塘个数。