POJ2718 贪心算法

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import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class SmallestDifference {

static int[] dig;static int[] n1;static int[] n2;static int len;public static void main(String[] args) throws FileNotFoundException {    // TODO Auto-generated method stub    Scanner sc = new Scanner(System.in);    sc = new Scanner(new File("src/file/smalldiff"));    int T = sc.nextInt();    String tmpaaa = sc.nextLine();    for (int t = 0; t < T; t++) {        String[] tmpread = sc.nextLine().split(" ");        len = tmpread.length;        dig = new int[len];        for (int i = 0; i < len; i++) {            dig[i] = Integer.valueOf(tmpread[i]);        }        if (len % 2 == 0) {            n1 = new int[len / 2];            n2 = new int[len / 2];            isEven();        } else {            n1 = new int[len / 2 + 1];            n2 = new int[len / 2];            unEven();        }    }}private static void unEven() {    // TODO Auto-generated method stub    for (int i = 0; i < n1.length; i++) {        n1[i] = dig[i];    }    for (int i = 0; i < n2.length; i++) {        n2[i] = dig[len - i - 1];    }    if (n1[0] == 0) {        int tmp = n1[0];        n1[0] = n1[1];        n1[1] = tmp;    }    System.out.println(Printf());}private static void isEven() {    // TODO Auto-generated method stub    if (len == 2) {        n1[0] = dig[1];        n2[0] = dig[0];        System.out.println(Printf());    } else if (len == 10) {        System.out.println(247);    } else {        int min = 10;        int count = 0;        int seq[] = new int[len];        int tmpi;        if (dig[0] == 0)            tmpi = 2;        else            tmpi = 1;        for (int i = tmpi; i < len; i++) {            int di = dig[i] - dig[i - 1];            if (di < min) {                min = di;                seq[i] = min;                count = 1;            } else if (di == min) {                seq[i] = min;                count++;            }        }        int mindif = 10;        int ti = 10;        for (int i = 1; i < len; i++) {            if (seq[i] == min) {                int tmpd = i > len / 2 ? i - len / 2 : len / 2 - i;                if (tmpd < mindif) {                    mindif = tmpd;                    ti = i;                }            }        }        n1[0] = dig[ti];        n2[0] = dig[ti - 1];        int tii = 1;        for (int i = 1; i < n1.length; i++) {            if (i == ti)                tii = -1;            n1[i] = dig[i - tii];        }        tii = 0;        for (int i = 1; i < n2.length; i++) {            if (len - i == ti)                tii = 2;            n2[i] = dig[len - i - tii];        }        System.out.println(Printf());    }}private static int Printf() {    // TODO Auto-generated method stub    int tmpn1 = 0;    int tmpn2 = 0;    for (int i = 0; i < n1.length; i++) {        tmpn1 = tmpn1 * 10 + n1[i];    }    for (int i = 0; i < n2.length; i++) {        tmpn2 = tmpn2 * 10 + n2[i];    }    return tmpn1 - tmpn2;}

}

sample input:
8
1 2 3 4 5
0 1 2 3 4 5 6 7 8 9
0 3 6 9
0 1 2 3 4 5 7 9
1 3 5 7 8 9
1 2 3 4 6 8
0 2
1 2 3 5 7 9

sample output:
69
247
21
37
18
26
2
18

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