1025 反转链表
给定一个常数 K 以及一个单链表 L,请编写程序将 L 中每 K 个结点反转。例如:给定 L 为 1→2→3→4→5→6,K 为 3,则输出应该为 3→2→1→6→5→4;如果 K 为 4,则输出应该为 4→3→2→1→5→6,即最后不到 K 个元素不反转。
输入格式:
每个输入包含 1 个测试用例。每个测试用例第 1 行给出第 1 个结点的地址、结点总个数正整数 N (≤105)、以及正整数 K (≤N),即要求反转的子链结点的个数。结点的地址是 5 位非负整数,NULL 地址用 −1 表示。
接下来有 N 行,每行格式为:
Address Data Next
Address Data Next
其中 Address
是结点地址,Data
是该结点保存的整数数据,Next
是下一结点的地址。
输出格式:
对每个测试用例,顺序输出反转后的链表,其上每个结点占一行,格式与输入相同。
输入样例:
tex
00100 6 4
00000 4 99999
00100 1 12309
68237 6 -1
33218 3 00000
99999 5 68237
12309 2 33218
00100 6 4
00000 4 99999
00100 1 12309
68237 6 -1
33218 3 00000
99999 5 68237
12309 2 33218
输出样例:
tex
00000 4 33218
33218 3 12309
12309 2 00100
00100 1 99999
99999 5 68237
68237 6 -1
00000 4 33218
33218 3 12309
12309 2 00100
00100 1 99999
99999 5 68237
68237 6 -1
Solution:
WARNING
测试点 5 运行超时
DANGER
测试点 6 答案错误
java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StreamTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
StreamTokenizer in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
in.nextToken();
int[] list = new int[100001];
int[] data = new int[100001];
int[] next = new int[100001];
int first = (int) in.nval;
in.nextToken();
int n = (int) in.nval;
in.nextToken();
int k = (int) in.nval;
for (int i = 0; i < n; i++) {
in.nextToken();
int address = (int) in.nval;
in.nextToken();
data[address] = (int) in.nval;
in.nextToken();
next[address] = (int) in.nval;
}
int sum = 0;
while (first != -1) {
list[sum++] = first;
first = next[first];
}
for (int i = 0; i < (sum - sum % k); i += k) {
int len = i + k;
int cnt = 0;
for (int j = i; j < (len - i) / 2 + i; j++) {
list[j] = list[j] + list[len - 1 - cnt] - (list[len - 1 - cnt] = list[j]);
cnt++;
}
}
StringBuilder sb = new StringBuilder();
for (int i = 0; i < n - 1; i++) {
sb.append(String.format("%05d %d %05d\n", list[i], data[list[i]], list[i + 1]));
}
sb.append(String.format("%05d %d -1", list[n - 1], data[list[n - 1]]));
System.out.print(sb);
}
}
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StreamTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
StreamTokenizer in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
in.nextToken();
int[] list = new int[100001];
int[] data = new int[100001];
int[] next = new int[100001];
int first = (int) in.nval;
in.nextToken();
int n = (int) in.nval;
in.nextToken();
int k = (int) in.nval;
for (int i = 0; i < n; i++) {
in.nextToken();
int address = (int) in.nval;
in.nextToken();
data[address] = (int) in.nval;
in.nextToken();
next[address] = (int) in.nval;
}
int sum = 0;
while (first != -1) {
list[sum++] = first;
first = next[first];
}
for (int i = 0; i < (sum - sum % k); i += k) {
int len = i + k;
int cnt = 0;
for (int j = i; j < (len - i) / 2 + i; j++) {
list[j] = list[j] + list[len - 1 - cnt] - (list[len - 1 - cnt] = list[j]);
cnt++;
}
}
StringBuilder sb = new StringBuilder();
for (int i = 0; i < n - 1; i++) {
sb.append(String.format("%05d %d %05d\n", list[i], data[list[i]], list[i + 1]));
}
sb.append(String.format("%05d %d -1", list[n - 1], data[list[n - 1]]));
System.out.print(sb);
}
}