C :

#include <stdio.h>

int main()
{
	int character = 1, i;
	char a[100];
	gets(a);
	for (i = 0;a[i] != '\0';i++)
		if (' ' == a[i])
			character++;
	printf("%d\n", character);
}

C++ :

#include<iostream>
using namespace std;
char s[101];
int main()
{
	cin.getline(s,101);
	char c;
	int num=0,word=0;
	for (int i=0; (c=s[i])!='\0'; i++)
		if (c==' ') word=0;
		else if (word==0)
		{
			num++;
			word=1;
		}
	cout<<num<<endl;
	return 0;
}

Java :

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		while(sc.hasNext()){
			String s=sc.nextLine();
			int n=1;
			for(int i=0;i<s.length();i++){
				if(s.substring(i, i+1).matches(" ")){
					n++;
				}
			}
			System.out.println(n);
		}
		sc.close();
	}
}