Question

我是java的新手，也是编程。我已经给出了一个计算唯一字符出现次数的作业。我只能用阵列。我做了流动的代码 -

public class InsertChar{

    public static void main(String[] args){

        int[] charArray = new int[1000];
        char[] testCharArray = {'a', 'b', 'c', 'x', 'a', 'd', 'c', 'x', 'a', 'd', 'a'};

        for(int each : testCharArray){

            if(charArray[each]==0){
                charArray[each]=1;
            }else{
                ++charArray[each];
            }

        }

        for(int i=0; i<1000; i++){
            if(charArray[i]!=0){
                System.out.println( i +": "+ charArray[i]);
            }
        }
    }

}

对于testCharArray，输出应为 -

a: 4
b: 1
c: 2
d: 2
x: 2

但它给了我以下的outpu -

我该如何解决这个问题？

Answer 1

2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: Running the test! 2015/05/31 00:41:23 INFO - jmeter.samplers.SampleEvent: List of sample_variables: [] 2015/05/31 00:41:23 INFO - jmeter.gui.util.JMeterMenuBar: setRunning(true,*local*) 2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: Starting ThreadGroup: 1 : Thread Group 2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: Starting 1 threads for group Thread Group. 2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: Thread will continue on error 2015/05/31 00:41:23 INFO - jmeter.threads.ThreadGroup: Starting thread group number 1 threads 1 ramp-up 0 perThread 0.0 delayedStart=false 2015/05/31 00:41:23 INFO - jmeter.threads.ThreadGroup: Started thread group number 1 2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: All thread groups have been started 2015/05/31 00:41:23 INFO - jmeter.threads.JMeterThread: Thread started: Thread Group 1-1 2015/05/31 00:41:23 INFO - jmeter.threads.JMeterThread: Thread is done: Thread Group 1-1 2015/05/31 00:41:23 INFO - jmeter.threads.JMeterThread: Thread finished: Thread Group 1-1 2015/05/31 00:41:23 INFO - jmeter.engine.StandardJMeterEngine: Notifying test listeners of end of test 2015/05/31 00:41:23 INFO - jmeter.gui.util.JMeterMenuBar: setRunning(false,*local*)为i，因此您要打印每个int的整数值。您必须将其强制转换为char才能看到字符。

变化

char

到

System.out.println( i +": "+ charArray[i]);

Answer 2

您正在将索引打印为System.out.println( (char)i +": "+ charArray[i]);。在打印之前尝试将其投射到int：

char

Answer 3

您的程序正在打印ascii字符表示。您只需将acsii数字转换为字符。

public class InsertChar{

    public static void main(String[] args){

        int[] charArray = new int[1000];
        char[] testCharArray = {'a', 'b', 'c', 'x', 'a', 'd', 'c', 'x', 'a', 'd', 'a'};

        for(int each : testCharArray){

            if(charArray[each]==0){
                charArray[each]=1;
            }else{
                ++charArray[each];
            }

        }

        for(int i=0; i<1000; i++){
            if(charArray[i]!=0){
                System.out.println( **(char)**i +": "+ charArray[i]);
            }
        }
    }

}

这应该有用。

进一步阅读：

How to convert ASCII code (0-255) to a String of the associated character?

Answer 4

您正在打印每个stop的{{1}} [NSArray arrayWithObjects: ... , nil];个代表。您必须通过强制转换将其转换为[NSNumber numberWith...]; -

#pragma mark

Answer 5

您的C:\Education\DataStructure_Algorithms\List\List.cpp|252| error: need 'typename' before 'std::unordered_set<Node<T>*>:: const_iterator' because 'std::unordered_set<Node<T>*>' is a dependent scope|是一个int数组。你已经存储了char。所以你必须将字符转换为int。您必须在最后一个循环中进行更改 -

testCharArray

此转换使int成为char。每个字符都有一个int值。例如 -

'a'有97，因为它是for(int i=0; i<1000; i++){ if(charArray[i]!=0){ System.out.println( (char)i +": "+ charArray[i]); //cast int to char. } }值
'b'有98，因为它是int值

打印独特的字符及其出现

5 个答案: