C :

#include<stdio.h>
int main(){
int word=0,num=0;
int i=0;
char c[100];
gets(c);
  while(c[i]!='\0'){
    if(c[i]==' ')
      word=0;
    else if(word==0){
      word=1;
      num++;}
    i++;
  }
printf("%d\n",num);
return 0;
}

C++ :

#include <stdio.h>
int main() {
	char buffer[101];
	int num = 0, i, word = 0;
	char c;
	gets(buffer);
	for (i = 0;(c = buffer[i]) != '\0';i++) {
		if (c == ' ')
			word = 0;
		else if (word == 0) {
			word = 1;
			num++;
		}
	}	
	printf("%d\n", num);
	return 0;
}

Pascal :

var ch:string;
  lt,wd,i:longint;
ss:set of char;
begin
  readln(ch);
  while ch[1]=' ' do delete(ch,1,1);
  ss:=[' ',',','.','?','!',':','"'];
  lt:=0;
  wd:=0;
  i:=0;
  repeat
    inc(i);
    if (ch[i] in ss) then
        begin if not (ch[i-1]in ss) then inc(wd) end else inc(lt);
  until (i=ord(ch[0]))or (ch[i] in ['.','!','?']);
  writeln(wd);
  //writeln(lt/wd:0:2);
end.

Java :

import java.util.Scanner;

class Main
{
    public static void main(String[] args)
    {
        String str;
        Scanner cin=new Scanner(System.in);
        while(cin.hasNext())
        {
            str=cin.nextLine();
            int ct=str.split(" ").length;
            System.out.println(ct);
        }
    }
}

Python :

print len(raw_input().split())