Question

struct DATA
{
int *pData;
int nSize;
int nSum;
int nMax;
int nMin;
float fMean;
};

struct DATA ReadDataFile(const char *pFileName);

int main(void)
{
DATA stData = ReadDataFile ("data.txt");
printf("We read %d numbers\n", stData.nSum);
printf("SUM: %d\nMEAN: %f\nMAX: %d\nMIN: %d\n",
(float)stData.nSum / stData.nSize, stData.nMax, stData.nMin); return 0;
}

如何将data.txt的值分配到*pData并计算nSum？我通过将值存储到数组中来完成它。但无法分配和完成使用指针？

我确实使用了如下数组。

if (infile.is_open())
    {
            while (infile.good())
            {
                    infile.getline(cNum, 256, ' ');
                    arrays[count]= atoi(cNum) ;
                    ++count ;
            }
            infile.close();
            min = arrays[0];
            max = arrays[0];
            for(int j=0; j<count; j++)
            {
                if(min > arrays[j])
                    min = arrays[j];
                if(max < arrays[j])
                    max = arrays[j];
                sum = sum + arrays[j];
            }
            mean = sum/count;
            cout<<"Sum= "<<sum<<"; Min= "<<min<<"; Max= "<<max<<"; Mean= "<<mean<<"\n";
    }

但是如何使用结构来做同样的事情？

Answer 1

Traceback (most recent call last): File "manage.py", line 10, in <module> execute_from_command_line(sys.argv) File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 338, in execute_from_command_line utility.execute() File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 330, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/test.py", line 30, in run_from_argv super(Command, self).run_from_argv(argv) File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 390, in run_from_argv self.execute(*args, **cmd_options) File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/test.py", line 74, in execute super(Command, self).execute(*args, **options) File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 441, in execute output = self.handle(*args, **options) File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/test.py", line 90, in handle failures = test_runner.run_tests(test_labels) File "/usr/local/lib/python2.7/dist-packages/django/test/runner.py", line 210, in run_tests old_config = self.setup_databases() File "/usr/local/lib/python2.7/dist-packages/django/test/runner.py", line 166, in setup_databases **kwargs File "/usr/local/lib/python2.7/dist-packages/django/test/runner.py", line 370, in setup_databases serialize=connection.settings_dict.get("TEST", {}).get("SERIALIZE", True), File "/usr/local/lib/python2.7/dist-packages/django/db/backends/base/creation.py", line 368, in create_test_db test_flush=not keepdb, File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 120, in call_command return command.execute(*args, **defaults) File "/usr/local/lib/python2.7/dist-packages/django/core/management/base.py", line 441, in execute output = self.handle(*args, **options) File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/migrate.py", line 179, in handle created_models = self.sync_apps(connection, executor.loader.unmigrated_apps) File "/usr/local/lib/python2.7/dist-packages/django/core/management/commands/migrate.py", line 317, in sync_apps cursor.execute(statement) File "/usr/local/lib/python2.7/dist-packages/django/db/backends/utils.py", line 64, in execute return self.cursor.execute(sql, params) File "/usr/local/lib/python2.7/dist-packages/django/db/utils.py", line 97, in __exit__ six.reraise(dj_exc_type, dj_exc_value, traceback) File "/usr/local/lib/python2.7/dist-packages/django/db/backends/utils.py", line 62, in execute return self.cursor.execute(sql) django.db.utils.ProgrammingError: relation "auth_user" does not exist应该是您动态分配的数组。获取文件的元素数量并分配大量内存：

pData

然后，您可以在文件中填入your_struct.pData = new int[your_struct.nSize];值，并使用数组计算总和，最大值，最小值和平均值。

当你完成它时，不要忘记int。

使用结构指针计算文件中的整数之和

1 个答案: