Knuth-Morris-Pratt Algorithm

[email protected] Sycamore, ZJNU
[email protected] 4/9/2017
#include <iostream>
#include <sstream>
#include <iomanip>
#include <cmath>
#include <string>
#include <algorithm>
#include <numeric>
#include <functional>
 

#include <vector>
#include <set>
#include <list>
#include <stack>
#include <queue>
#include <map>
#include <algorithm>
#include <cctype>
#include<fstream>
//#define cin fin
//#define cout fout
//ifstream fin("in.txt");
//ofstream fout("out.txt");
using namespace
 
 std;
typedef vector<int> VI;
typedef pair<int, int> PII;
int main()
{
	ios::sync_with_stdio(false);
	int T;
	cin >> T;
	while (T--)
	{
		string s;
		cin >> s;
		int c = 0, pos = 0;
		while (true)
		{
			int ppos = min(s.find("cat", pos), s.find("dog", pos));
			if (ppos < pos)
 
break;
			else
			{
				pos = ppos + 3;
				c++;
			}
		}
		cout << c << endl;
	}
	return 0;
}

ZOJ 3957: Knuth-Morris-Pratt Algorithm