立此存照(11)[C++]cfloat头文件即浮点数的最大值与最小值

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C++标准头文件cfloat存放着C++基本类型float，double，long double等基本类型的最大值与最小值，以及其他信息

1.编译环境:VS2008

#include <iostream>#include <iomanip>//needs setw#include <cfloat>using std::cout;using std::endl;using std::setw;using std::ios;int main(){const int COUT_WIDTH = 25;cout<<setiosflags(ios::left);//floatcout<<setw(COUT_WIDTH)<<"sizeof(float):"<<sizeof(float)<<endl;cout<<setw(COUT_WIDTH)<<"float Min:"<<FLT_MIN<<endl;cout<<setw(COUT_WIDTH)<<"float Max:"<<FLT_MAX<<endl<<endl;//doublecout<<setw(COUT_WIDTH)<<"sizeof(double):"<<sizeof(double)<<endl;cout<<setw(COUT_WIDTH)<<"double Min:"<<DBL_MIN<<endl;cout<<setw(COUT_WIDTH)<<"double Max:"<<DBL_MAX<<endl<<endl;//long doublecout<<setw(COUT_WIDTH)<<"sizeof(long double):"<<sizeof(long double)<<endl;cout<<setw(COUT_WIDTH)<<"long double Min:"<<LDBL_MIN<<endl;cout<<setw(COUT_WIDTH)<<"long double Max:"<<LDBL_MAX<<endl;return 0;}

执行结果:

编译环境:g++

2.编译环境:VC++6.0

#include <iostream>#include <iomanip>//needs setw#include <cfloat>using std::cout;using std::endl;using std::setw;using std::ios;int main(){const int COUT_WIDTH = 25;//cout<<setiosflags(ios::left);cout.setf(ios::left);//floatcout<<setw(COUT_WIDTH)<<"sizeof(float):"<<sizeof(float)<<endl;cout<<setw(COUT_WIDTH)<<"float Min:"<<FLT_MIN<<endl;cout<<setw(COUT_WIDTH)<<"float Max:"<<FLT_MAX<<endl<<endl;//doublecout<<setw(COUT_WIDTH)<<"sizeof(double):"<<sizeof(double)<<endl;cout<<setw(COUT_WIDTH)<<"double Min:"<<DBL_MIN<<endl;cout<<setw(COUT_WIDTH)<<"double Max:"<<DBL_MAX<<endl<<endl;//long doublecout<<setw(COUT_WIDTH)<<"sizeof(long double):"<<sizeof(long double)<<endl;cout<<setw(COUT_WIDTH)<<"long double Min:"<<LDBL_MIN<<endl;cout<<setw(COUT_WIDTH)<<"long double Max:"<<LDBL_MAX<<endl;return 0;}

运行结果:

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