Cod sursa(job #2912049)

Utilizator BlaugranasEnal Gemaledin Blaugranas Data 6 iulie 2022 18:12:11
Problema Aria Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.27 kb
Raporteaza aceasta sursa 
#include<cstdio>
long double a,b,x,y,w,z,s,n;
int main()
{
    freopen("aria.in","r",stdin),freopen("aria.out","w",stdout),scanf("%Lf%Lf%Lf",&n,&a,&b);
    for(x=a,y=b;n;scanf("%Lf%Lf",&w,&z),s+=x*z-w*y,--n,x=w,y=z);
    return s+=x*b-a*y,printf("%.5Lf",s/2),0;
}