Me he puesto por fin a aprender Java. Asi que con un buen libro y con ejemplos como topcoder que mas quieres.

Despues de cansarme ya del libro y ver lo basico he decidido ir a por un algoritmo sencillo de topcoder.


PROBLEM STATEMENT
Proposals arrive at our office in a sequence. We give each one a score. We then
calculate its "rank" based on comparison with the scores of the most recent submissions.
Its rank is 1 + the number of recent scores that are greater than it. So a rank of 1
is the best possible rank and indicates that no recent score was greater. A rank of 2
would mean that exactly one recent score was greater.
We need software that can calculate the rank of each score.

Each rank should be calculated based on the preceding k scores. If fewer
than k scores have preceded this score, base the calculation on all the preceding
scores. (The first proposal is thus guaranteed a rank of 1.)


El problema es sencillo. Recibes un vector con numero y otro numero que te dice la cantidad de scores recientes. Tienes que calcular individualmente en cada elemento del vector e ir acumulando el resultado. Facil para empezar.


import java.util.*;
public class OnLineRank {
public int calcRanks(int k, int[] scores) {
int rankT = 0;

for(int i = 0; i < scores.length; i++){
int rank = 1;
for(int j = Math.max(0,i-k); j < i; j++){
if(scores[j] > scores[i]) rank++;
}
rankT += rank;
}
return rankT;
}
}