#include <stdio.h> #include <math.h> int main() { int x1, y1, x2, y2, a, b; float distance scanf("%d %d %d %d", &x1, &y1, &x2, &y2); a = x1 - x2; b = y1 - y2; distance = sqrt( a * a + b * b); printf("%.2f", distance); return 0; }