#include <stdio.h>
#include <math.h>
 
typedef struct{
    double vx; //x value
    double vy; //y value
} TVector;
 
typedef struct{
    double x; //x value
    double y; //y value
} TPoint;
 
double Vektorlaenge(TVector* V){return sqrt(V->vx*V->vx + V->vy*V->vy);}
 
TVector GetVector(TPoint* P2, TPoint* P1){
TVector V;
V.vx = P2->x - P1->x;
V.vy = P2->y - P1->y;
return V;
}
 
 
int main(){
TPoint P1, P2;
TVector V;
 
P1.x = .0;
P1.y = .0;
 
P2.x=1.;
P2.y=1.;
 
V = GetVector(&P2, &P1);
printf("Vektorlaenge: %2.4f\n", Vektorlaenge(&V));
 
getchar();
return 0;
}

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