C++ 关系运算符

尝试以下示例以了解C++中可用的所有关系运算符。

将下面的C++程序复制粘贴到test.cpp文件中，然后编译和运行该程序。

#include <iostream>
using namespace std;

main() {
   int a = 21;
   int b = 10;
   int c ;

   if( a == b ) {
      cout << "Line 1 - a is equal to b" << endl ;
   } else {
      cout << "Line 1 - a is not equal to b" << endl ;
   }

   if( a < b ) {
      cout << "Line 2 - a is less than b" << endl ;
   } else {
      cout << "Line 2 - a is not less than b" << endl ;
   }

   if( a > b ) {
      cout << "Line 3 - a is greater than b" << endl ;
   } else {
      cout << "Line 3 - a is not greater than b" << endl ;
   }

   /* Let's change the values of a and b */
   a = 5;
   b = 20;
   if( a <= b ) {
      cout << "Line 4 - a is either less than \ or equal to  b" << endl ;
   }

   if( b >= a ) {
      cout << "Line 5 - b is either greater than \ or equal to b" << endl ;
   }

   return 0;
}

当以上代码被编译和执行时，它会产生以下结果 –

Line 1 - a is not equal to b
Line 2 - a is not less than b
Line 3 - a is greater than b
Line 4 - a is either less than or euqal to  b
Line 5 - b is either greater than or equal to b