Problem:
Distance

Write a program which calculates the distance between two points P1(x1, y1) and P2(x2, y2).

Input

Four real numbers x1, y1, x2 and y2 are given in a line.

Output

Print the distance in real number. The output should not contain an absolute error greater than 10-4.

Sample Input

0 0 1 1

Sample Output

1.41421356

Solution in C (judge verdict: Time Limit Exceeded)

 #include <stdio.h> 
 #include <ctype.h> 
 #include <string.h> 


 int main(){ 
    char search[21], word[21]; 
    int count=0; 
    int i; 

    scanf("%s", search); 
    while(1){ 
        scanf(" %s", word); 
        if(strcmp(word, "END_OF_TEXT")==0)break; 
        for(i=0;word[i]!='\0';i++){ 
            word[i]=tolower(word[i]); 
        } 
        if(strcmp(word, search)==0){ 
            count++; 
        } 
    } 
    printf("%d\n", count); 


    return 0; 
 }