VS Code问题20200510--(numeric_limits::min)()无法使用

[德赛法]

问题：(numeric_limits<char>::min)()等函数无法显示后续文字。

源码：

#include <iostream>
using namespace std;
 
// 变量声明
extern int a, b;
extern int c;
extern float f;
  
int main ()
{
  // 变量定义
  int a, b;
  int c;
  float f;
 
  // 实际初始化
  a = 10;
  b = 20;
  c = a + b;
 
  cout << c << endl ;
 
  f = 70.0/3.0;
  cout << f << endl ;
 
  return 0;
}

结果：


明显不对。
我注释掉以下代码却能够显示后面的结果。

    // cout << "char: \t\t" << "所占字节数：" << sizeof(char);  
    // cout << "\t最大值：" << (numeric_limits<char>::max)();  //(numeric_limits<char>::min)()无法使用
    // cout << "\t\t最小值：" << (numeric_limits<char>::min)() << endl;  
    // cout << "signed char: \t" << "所占字节数：" << sizeof(signed char);  
    // cout << "\t最大值：" << (numeric_limits<signed char>::max)();  
    // cout << "\t\t最小值：" << (numeric_limits<signed char>::min)() << endl;  
    // cout << "unsigned char: \t" << "所占字节数：" << sizeof(unsigned char);  
    // cout << "\t最大值：" << (numeric_limits<unsigned char>::max)();  
    // cout << "\t\t最小值：" << (numeric_limits<unsigned char>::min)() << endl;  //本程序无法识别unsigned char大小，会出错

查找了<limits>头文件,里面关于char函数有定义，请问这是怎么回事？

[真相重于对错]

没看懂你要问什么？？？？ 第一段代码和后面有何联系？？？？ unsigned char 最大 肯定打印不出来啊。

[德赛法]

糟糕，头脑晕了，多谢”真相重于对错“提醒。代码复制错了，第一段代码应该是下图代码。

#include<iostream>  
#include <limits>
 
using namespace std;  
  
int main()  
{  
    cout << "type: \t\t" << "************size**************"<< endl;  
    cout << "bool: \t\t" << "所占字节数：" << sizeof(bool);  
    cout << "\t最大值：" << (numeric_limits<bool>::max)();  
    cout << "\t\t最小值：" << (numeric_limits<bool>::min)() << endl;  
    cout << "char: \t\t" << "所占字节数：" << sizeof(char);  
    cout << "\t最大值：" << (numeric_limits<char>::max)();  //(numeric_limits<char>::min)()无法使用
    cout << "\t\t最小值：" << (numeric_limits<char>::min)() << endl;  
    cout << "signed char: \t" << "所占字节数：" << sizeof(signed char);  
    cout << "\t最大值：" << (numeric_limits<signed char>::max)();  
    cout << "\t\t最小值：" << (numeric_limits<signed char>::min)() << endl;  
    cout << "unsigned char: \t" << "所占字节数：" << sizeof(unsigned char);  
    cout << "\t最大值：" << (numeric_limits<unsigned char>::max)();  
    cout << "\t\t最小值：" << (numeric_limits<unsigned char>::min)() << endl;  //本程序无法识别unsigned char大小，会出错
    cout << "wchar_t: \t" << "所占字节数：" << sizeof(wchar_t);  
    cout << "\t最大值：" << (numeric_limits<wchar_t>::max)();  
    cout << "\t\t最小值：" << (numeric_limits<wchar_t>::min)() << endl;  
    cout << "short: \t\t" << "所占字节数：" << sizeof(short);  
    cout << "\t最大值：" << (numeric_limits<short>::max)();  
    cout << "\t\t最小值：" << (numeric_limits<short>::min)() << endl;  
    cout << "int: \t\t" << "所占字节数：" << sizeof(int);  
    cout << "\t最大值：" << (numeric_limits<int>::max)();  
    cout << "\t最小值：" << (numeric_limits<int>::min)() << endl;  
    cout << "unsigned: \t" << "所占字节数：" << sizeof(unsigned);  
    cout << "\t最大值：" << (numeric_limits<unsigned>::max)();  
    cout << "\t最小值：" << (numeric_limits<unsigned>::min)() << endl;  
    cout << "long: \t\t" << "所占字节数：" << sizeof(long);  
    cout << "\t最大值：" << (numeric_limits<long>::max)();  
    cout << "\t最小值：" << (numeric_limits<long>::min)() << endl;  
    cout << "unsigned long: \t" << "所占字节数：" << sizeof(unsigned long);  
    cout << "\t最大值：" << (numeric_limits<unsigned long>::max)();  
    cout << "\t最小值：" << (numeric_limits<unsigned long>::min)() << endl;  
    cout << "double: \t" << "所占字节数：" << sizeof(double);  
    cout << "\t最大值：" << (numeric_limits<double>::max)();  
    cout << "\t最小值：" << (numeric_limits<double>::min)() << endl;  
    cout << "long double: \t" << "所占字节数：" << sizeof(long double);  
    cout << "\t最大值：" << (numeric_limits<long double>::max)();  
    cout << "\t最小值：" << (numeric_limits<long double>::min)() << endl;  
    cout << "float: \t\t" << "所占字节数：" << sizeof(float);  
    cout << "\t最大值：" << (numeric_limits<float>::max)();  
    cout << "\t最小值：" << (numeric_limits<float>::min)() << endl;  
    cout << "size_t: \t" << "所占字节数：" << sizeof(size_t);  
    cout << "\t最大值：" << (numeric_limits<size_t>::max)();  
    cout << "\t最小值：" << (numeric_limits<size_t>::min)() << endl;  
    cout << "string: \t" << "所占字节数：" << sizeof(string) << endl;  
    // << "\t最大值：" << (numeric_limits<string>::max)() << "\t最小值：" << (numeric_limits<string>::min)() << endl;  
    cout << "type: \t\t" << "************size**************"<< endl;  
    return 0;  
}

[56625079]

试试加上+号。我就是这么解决的

cout << "char: \t\t\t" << "numOfBytes:" << sizeof(char);
cout << "\t\tmaxValue:" << +(numeric_limits<char>::max)();
cout << "\t\t\t\tminValue:" << +(numeric_limits<char>::min)() << endl;

cout << "signed char: \t\t" << "numOfBytes:" << sizeof(signed char);
cout << "\t\tmaxValue:" << +(numeric_limits<signed char>::max)();
cout << "\t\t\t\tminValue:" << +(numeric_limits<signed char>::min)() << endl;

cout << "unsigned char: \t\t" << "numOfBytes:" << sizeof(unsigned char);
cout << "\t\tmaxValue:" << +(numeric_limits<unsigned char>::max)();
cout << "\t\t\t\tminValue:" << +(numeric_limits<unsigned char>::min)() << endl;

[真相重于对错]

numeric_limits 类模板提供查询各种算术类型属性的标准化方式（例如 int 类型的最大可能值是 std::numeric_limits<int>::max() ）。 string 又不是算术类型。

[真相重于对错]

unsigned char 的最大值，最小值都不是可打印字符，自然也无法打印]