试题 算法训练 My Bad
问题描述
一个逻辑电路将其输入通过不同的门映射到输出,在电路中没有回路。输入和输出是一个逻辑值的有序集合,逻辑值被表示为1和0。我们所考虑的电路由与门(and gate,只有在两个输入都是1的时候,输出才为1)、或门(or gate,只要两个输入中有一个是1,输出就是1)、异或门(exclusive or(xor)gate,在两个输入中仅有一个是1,输出才是1)和非门(not gate,单值输入,输出是输入的补)组成。下图给出两个电路。
不幸的是,在实际中,门有时会出故障。虽然故障会以多种不同的方式发生,但本题将门会出现的故障限于如下三种形式之一:
1)总是与正确的输出相反;
2)总是产生0;
3)总是产生1;
在本题给出的电路中,最多只有一个门出故障。
请编写一个程序,对一个电路进行分析,对多组输入和输出进行实验,看电路运行是正确的还是不正确的。如果至少有一组输入产生了错误的输出,程序要确定唯一的出故障的门,以及这个门出故障的方式。但这也可能是无法判断的。
输入格式
输入由多组测试数据组成,每组测试用例描述了一个电路及其输入和输出。每个测试数据按序给出下述部分。
1. 一行给出3个正整数:在电路中输入的数量(N ≤ 8),门的数量(G ≤ 19)和输出的数量(U ≤ 19)。
2. 每行一个门,第一行描述g1门,如果有若干个门,则下一行描述g2门,以此类推。每行给出门类型(a = and,n = not,o = or,x = exclusive or)和对这个门的所有输入的标识符,对这个门的输入来自电路输入(i1, i2, …)或来自另一个门的输出(g1, g2, …)。
3. 一行给出与U个输出u1, u2, ….所关联的门的编号。例如,如果有三个输出,u1来自g5,u2来自g1,u3来自g4,那么这一行为:5 1 4。
4. 一行给出一个整数,表示对电路的进行实验的次数(B)。
5. 最后给出B行,每行(N+U)个值(1和0),给出实验的输入值和相应的输出值。不存在有两个相同输入的情况。
输入中的标识符或数字以空格分开,输入以包含3个0的一行结束。
输出格式
对于输入数据中的每个电路,输出测试数据的编号(从1开始),然后输出一个冒号和一个空格,再输出电路分析,内容为如下之一(用#代替相应的门的编号):
No faults detected
Gate # is failing; output inverted
Gate # is failing; output stuck at 0
Gate # is failing; output stuck at 1
Unable to totally classify the failure
在图1和图2 中给出的电路图是第一个和最后一个测试数据。
样例输入
2 2 1
o i1 i2
n g1
2
2
1 0 0
0 0 1
2 1 1
a i1 i2
1
1
1 0 1
2 1 1
a i1 i2
1
2
1 0 1
1 1 1
1 1 1
n i1
1
2
1 1
0 0
3 4 4
n g4
a i1 i2
o i2 i3
x i3 i1
2 3 4 1
4
0 1 0 0 1 0 1
0 1 1 0 1 1 0
1 1 1 0 1 0 1
0 0 0 0 0 0 1
0 0 0
样例输出
Case 1: No faults detected
Case 2: Unable to totally classify the failure
Case 3: Gate 1 is failing; output stuck at 1
Case 4: Gate 1 is failing; output inverted
Case 5: Gate 2 is failing; output stuck at 0
数据规模和约定
N<=8;G,U<=19
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
// 转自: https://blog.csdn.net/a1439775520
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
StringTokenizer tokenizer = new StringTokenizer("");
int kk = 0;
while (true) {
tokenizer = new StringTokenizer(reader.readLine());
int in = Integer.parseInt(tokenizer.nextToken());
int door = Integer.parseInt(tokenizer.nextToken());
int out = Integer.parseInt(tokenizer.nextToken());
if (in == 0 && door == 0 && out == 0)
break;
kk++;
System.out.printf("Case %d: ", kk);
Door d[] = new Door[20];
for (int i = 1; i <= door; i++) {
tokenizer = new StringTokenizer(reader.readLine());
String kind = tokenizer.nextToken();
int incont = 2;
if (kind.equals("n"))
incont = 1;
int kinda = -1;
if (kind.equals("a"))
kinda = 1;
else if (kind.equals("o"))
kinda = 2;
else if (kind.equals("x"))
kinda = 3;
else if (kind.equals("n"))
kinda = 4;
String aa = tokenizer.nextToken();
int ina = Integer.parseInt(aa.substring(1));
// System.out.println("ina :" + ina);
if (aa.charAt(0) == 'i')
ina = -ina;
int inb = 0;
if (incont == 2) {
String bb = tokenizer.nextToken();
inb = Integer.parseInt(bb.substring(1));
// System.out.println("inb :" + inb);
if (bb.charAt(0) == 'i')
inb = -inb;
}
d[i] = new Door(i, kinda, ina, inb);
}
boolean[] visit = new boolean[60];
for (int i = 0; i <= 3 * door; i++)
visit[i] = true;
int[] s = new int[20];
int[] o = new int[20];
int conts = 0;
for (int i = 1; i <= door; i++) {
int inta = d[i].ina;
int intb = d[i].inb;
if (inta > 0)
d[inta].addout(i);
if (intb > 0)
d[intb].addout(i);
if (inta <= 0 && intb <= 0)
s[conts++] = i;
}
tokenizer = new StringTokenizer(reader.readLine());
for (int i = 0; i < out; i++)
o[i] = Integer.parseInt(tokenizer.nextToken());
int test = Integer.parseInt(reader.readLine());
int[] ins = new int[10];
String outs = "";
String res = "";
for (int i = 0; i < test; i++) {
tokenizer = new StringTokenizer(reader.readLine());
for (int j = 1; j <= in; j++)
ins[j] = Integer.parseInt(tokenizer.nextToken());
outs = "";
for (int j = 0; j < out; j++)
outs += tokenizer.nextToken();
for (int cas = 0; cas <= 3 * door; cas++) {
if (visit[cas]) {
for (int j = 1; j <= door; j++)
d[j].cont = d[j].have = 0;
for (int j = 0; j < conts; j++) {
int id = s[j];
d[id].cal(ins, d, cas);
}
res = "";
for (int j = 0; j < out; j++)
res += String.valueOf(d[o[j]].value);
if (outs.equals(res) == false)
visit[cas] = false;
}
}
}
if(visit[0] == true)
System.out.println("No faults detected");
else {
int one = -1;
boolean mark = true;
for(int i = 0; i<=3*door; i++) {
if(visit[i] == true)
{
if(one == -1)
one = i;
else
{
mark = false;
break;
}
}
}
if(mark) {
int id = (one-1)/3 + 1;
int r = one%3;
if(r == 0)
r+=3;
if(r == 1)
System.out.printf("Gate %d is failing; output inverted
", id);
else if(r == 2)
System.out.printf("Gate %d is failing; output stuck at 0
", id);
else if(r == 3)
System.out.printf("Gate %d is failing; output stuck at 1
", id);
}
else
System.out.println("Unable to totally classify the failure");
}
}
}
}
class Door {
int id;
int incont;
int cont;
int ina, inb;
int kind;
int outcont;
int va, vb, value;
int[] out = new int[20];
int have;
public Door(int id_, int kind_, int ina_, int inb_) {
id = id_;
kind = kind_;
ina = ina_;
inb = inb_;
incont = 0;
if (ina > 0)
incont++;
if (inb > 0)
incont++;
outcont = cont = have = 0;
}
public void addout(int num) {
out[outcont++] = num;
}
public void cal(int[] ins, Door[] d, int cas) {
if (ina < 0)
va = ins[-ina];
else if (ina > 0)
va = d[ina].value;
if (inb < 0)
vb = ins[-inb];
else if (inb > 0)
vb = d[inb].value;
if (kind == 1)
value = va & vb;
else if (kind == 2)
value = va | vb;
else if (kind == 3)
value = va ^ vb;
else if (kind == 4)
value = va == 0 ? 1 : 0;
if (cas != 0 && (cas - 1) / 3 + 1 == id) {
int r = cas % 3;
if (r == 0)
r = 3;
if (r == 1)
value = value == 0 ? 1 : 0;
else if (r == 2)
value = 0;
else if (r == 3)
value = 1;
}
update(ins, d, cas);
}
public void update(int[] ins, Door[] d, int r) {
for (int i = 0; i < outcont; i++) {
d[out[i]].cont++;
if (d[out[i]].cont == d[out[i]].incont) {
d[out[i]].cal(ins, d, r);
}
}
}
}