我有一个任务，生产煎饼，用户也可以同时吃它。条件是30秒内只能制作12个煎饼。我遇到的问题是，当煎饼被生产出来时，用户正在按预期吃它，但是当它生产出最后一个煎饼（即第 12 个）时，它会在用户没有吃掉它的情况下终止，从而浪费了 1 个煎饼。我的最终输出是：
Total number of cake produced is 12
Total number of cake eaten is 11
Total number of pancake remained is 1
public class PanCakeTask {
int consumedPancake;
int availablePancake;
int totalPancakeProduced;
List<String> usersList = new ArrayList<>();
void producePancake(HashMap<String,Integer>users){
consumedPancake =0;
availablePancake = 0;
totalPancakeProduced = 0;
if ( totalPancakeProduced <12) {
for (String user: users.keySet()){
consumedPancake +=users.get(user);
}
//only continue with the production of pancakes if the number of pancakes
//produced has not exceeded the quota that was given (i.e 12)
System.out.println("Pancake produced");
//increment the number of pancakes available
availablePancake +=1;
totalPancakeProduced = consumedPancake + availablePancake;
eatPancake(users);
}
}
void eatPancake(HashMap<String,Integer>users){
if (usersList.size()>=1){
System.out.println("The list is "+usersList);
//first pick the user at random
Collections.shuffle(usersList)
int numberEaten = users.get(usersList.get(0));
//get the user that is on index zero after the list has been shuffled
//then check how many pancake that the picked user has eaten
//because each user is expected to eat a maximum of 5 pancake
if (numberEaten >=5){
//This means that this user has exhausted his/her quota so he/she cannot
//be allowed to eat again
//In this case, the eatPancake method is called again to randomly pick another user
//I am thinking of removing the user from the list here so that he/she cannot be picked again
usersList.remove(0);
eatPancake(users);
}else {
//Meaning that the user still has some quota left for him/her to eat
//In this other condition, it will check if there is an available pancake produced
if (availablePancake >=1){
//user will now eat the pancake
//then increment the number of pancake eaten by that user
// and decrement the number of pancakes available
int newCount = numberEaten + 1;
availablePancake -=1;
//finally update the user that just eaten the pancake
users.put(usersList.get(0),newCount);
}
}
}
}
public void performTask(){
//Hashmap is used to store the users because of key-value pairs
HashMap <String,Integer> users = new HashMap<>();
users.put("user1",0);
users.put("user2",0);
users.put("user3",0);
usersList.addAll(users.keySet());
System.out.println(users);
System.out.println(usersList);
//This task can only be executed in 20 seconds
Instant stop = Instant.now().plusSeconds(20);
System.out.println("The starting time is "+Instant.now());
while (stop.isAfter(Instant.now())){
//only continue the process if it has not exceeded 20 seconds
if (totalPancakeProduced <12){
producePancake(users);
}else {
break;
}
}
int available = totalPancakeProduced - consumedPancake;
int numbersLeftToMeetTheDemand = totalPancakeProduced - 15;
System.out.println("The ending time is "+Instant.now());
System.out.println("Total number of cake produced is "+totalPancakeProduced);
System.out.println("Total number of cake eaten is "+consumedPancake);
System.out.println("Total number of pancake remained is "+available);
}
您仅在
consumedPancakeproducePancake当循环到达最后一次迭代时，这将是一个问题。因为，
producePancakeconsumedPancakeuserseatPancakeconsumedPancakeeatPancake要解决此问题，不要在
consumedPancakeproducePancakeeatPancake像这样：
void eatPancake(HashMap<String,Integer>users){
if (usersList.size()>=1){
System.out.println("The list is "+usersList);
//first pick the user at random
Collections.shuffle(usersList)
int numberEaten = users.get(usersList.get(0));
//get the user that is on index zero after the list has been shuffled
//then check how many pancake that the picked user has eaten
//because each user is expected to eat a maximum of 5 pancake
if (numberEaten >=5){
//This means that this user has exhausted his/her quota so he/she cannot
//be allowed to eat again
//In this case, the eatPancake method is called again to randomly pick another user
//I am thinking of removing the user from the list here so that he/she cannot be picked again
usersList.remove(0);
eatPancake(users);
}else {
//Meaning that the user still has some quota left for him/her to eat
//In this other condition, it will check if there is an available pancake produced
if (availablePancake >=1){
//user will now eat the pancake
//then increment the number of pancake eaten by that user
// and decrement the number of pancakes available
int newCount = numberEaten + 1;
availablePancake -=1;
//finally update the user that just eaten the pancake
users.put(usersList.get(0),newCount);
//here
consumedPancake++;
}
}
}
}
amd 从 ProducePancake 中删除：
void producePancake(HashMap<String,Integer>users){
//consumedPancake =0;
availablePancake = 0;
totalPancakeProduced = 0;
if ( totalPancakeProduced <12) {
/*
for (String user: users.keySet()){
consumedPancake +=users.get(user);
}
*/
//only continue with the production of pancakes if the number of pancakes
//produced has not exceeded the quota that was given (i.e 12)
System.out.println("Pancake produced");
//increment the number of pancakes available
availablePancake +=1;
totalPancakeProduced = consumedPancake + availablePancake;
eatPancake(users);
}
}
此外，您的代码中有一些冗余部分，但这似乎不是问题的原因，因此忽略它们。