import java.io.*;
import java.util.regex.*;

// 処理
class Process {
    private String S;

    Process(String S) {
        this.S = S;
    }

    int getResult() {
        Matcher matcher = Pattern.compile("mi-*n").matcher(S);

        int count = 0;
        while(matcher.find()) {
            count++;
        }

        return count;
    }
}

public class Main {
    public static void main(String[] args) throws IOException {
        var bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        var printWriter    = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

        // 入力
        String S = bufferedReader.readLine().trim();

        // 出力
        printWriter.println((new Process(S)).getResult());

        bufferedReader.close();
        printWriter.close();
    }
}