Cod sursa(job #67507)
Utilizator | Data | 25 iunie 2007 10:43:16 | |
---|---|---|---|
Problema | P-sir | Scor | 0 |
Compilator | cpp | Status | done |
Runda | preONI 2007, Runda Finala, Clasele 11-12 | Marime | 0.5 kb |
#include<stdio.h>
int a[2001],i,j,k,n;
unsigned long nr[2001],N;
int sgn(int x,int y)
{if(x<y) return -1;
if(x==y) return 0;
return 1;}
int main()
{freopen("psir.in","r",stdin);
freopen("psir.out","w",stdout);
scanf("%d",&n);
for(i=1;i<=n;i++)
scanf("%d",&a[i]);
for(i=1;i<n-1;i++)
for(j=i+1;j<n;j++)
for(k=j+1;k<=n;k++)
if((sgn(a[k],a[i])*sgn(a[k],a[j])) < 0) nr[k]+=nr[i]+1;
N=n*(n-1)/2;
for(i=1;i<=n;i++)
N=N+nr[i];
printf("%d",N);
fclose(stdout);
return 0;}