1.A + B control problems // EOF
#include <iostream>
using namespace std; // C ++ header files
{
int a,b;
while (cin >> a >> b) // corresponds to the C language while (scanf ( "% d% d", & a, & b)! = EOF)
{
cout << a + b << endl; // output and a + b, endl corresponds to the C language \ n
}
return 0;
}
Wherein the output can be written: cout << "sum =" << a + b << endl; (need to define in advance sum).
Note cin followed by ">>", cout followed by "<<."
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2. EOF judgment
1.while((scanf"%d,%d",&m,&n)==2)
{
//...
}
2.while((scanf"%d,%d",&m,&n)!=EOF)
{
//...
}
3.while(cin>>m>>n)
{
//...
}
(Scanf ( "% d% d", & n, & m), n + m) - This is a "comma" expression.
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3. The output control precision
In C ++, there is no format breaks, we can achieve this demand through the use of setprecision () function.
Want to use setprecision () function, you must include the header file #include <iomanip>. Used as follows:
cout << "a=" << setprecision(2) << a <<endl;
At this time, we will find, if a value of 0.20001, the output result is a = 0.2, 0 are omitted second later.
If we want it to automatically fill 0, 0 patch needs to be defined prior to cout. code show as below:
cout.setf(ios::fixed);
cout << "a=" <<fixed<< setprecision(2) << a <<endl; //输出a=0.20
In this way, we can get a 0.20. Of course, if you want to close off the fill 0, only need to be fixed cancel the setting operation.
cout.unsetf(ios::fixed);
cout << "a=" << setprecision(2) << a <<endl; //输出a=0.2
Our output will then change back to a = 0.2 a.