How do I perform a mod operation between two integers in C++?
如何在C ++中的两个整数之间执行mod操作?
6 个解决方案
#1
10
Like this: x=y%z
像这样:x = y%z
#3
10
As the other answers have stated, you can use the C++ % operator. But be aware that there's a wrinkle no one has mentioned yet: in the expression a % b
, what if a
is negative? Should the result of this operation be positive or negative? The C++ standard leaves this up to the implementation. So if you want to handle negative inputs portably, you should probably do something like r = abs(a) % b
, then fix up the sign of r
to match your requirements.
正如其他答案所述,您可以使用C ++%运算符。但请注意,还没有人提到过的皱纹:在表达式a%b中,如果a是负面的怎么办?这项行动的结果应该是积极的还是消极的? C ++标准将此归结为实现。因此,如果您想要便携地处理负输入,您应该执行类似r = abs(a)%b的操作,然后修复r的符号以符合您的要求。
#4
9
C++ has the %
operator, occasionally and misleadingly named "the modulus" operator. In particular the STL has the modulus<>
functor in the <functional>
header. That's not the mathematical modulus operator, mind you, because in modulus arithmetics a mod b
by definition evaluates to a non-negative value for any value of a
and any positive value of b
. In C++ the sign of the result of a % b
is implementation-defined if either of the arguments is negative. So, we would more appropriately name the %
operator the remainder operator.
C ++有%运算符,偶尔会误导性地命名为“模数”运算符。特别是STL在
That said, if you truly want the mathematical modulus operator then you can define a function to do just that:
也就是说,如果你真的想要数学模数运算符,那么你可以定义一个函数来做到这一点:
template<typename V>
V mod(const V& a, const V& b)
{
return (a % b + b) % b;
}
So long as b
is a positive value a call to the above function will yield a non-negative result.
只要b是正值,对上述函数的调用将产生非负结果。
#5
2
Using the modulus %
operator :
使用模数%运算符:
int modulus_a_b = a % b;
#6
0
if you use double variable, you should use;
如果你使用双变量,你应该使用;
double x;
double y;
double result = fmod(x, y);
#1
10
Like this: x=y%z
像这样:x = y%z
#2
#3
10
As the other answers have stated, you can use the C++ % operator. But be aware that there's a wrinkle no one has mentioned yet: in the expression a % b
, what if a
is negative? Should the result of this operation be positive or negative? The C++ standard leaves this up to the implementation. So if you want to handle negative inputs portably, you should probably do something like r = abs(a) % b
, then fix up the sign of r
to match your requirements.
正如其他答案所述,您可以使用C ++%运算符。但请注意,还没有人提到过的皱纹:在表达式a%b中,如果a是负面的怎么办?这项行动的结果应该是积极的还是消极的? C ++标准将此归结为实现。因此,如果您想要便携地处理负输入,您应该执行类似r = abs(a)%b的操作,然后修复r的符号以符合您的要求。
#4
9
C++ has the %
operator, occasionally and misleadingly named "the modulus" operator. In particular the STL has the modulus<>
functor in the <functional>
header. That's not the mathematical modulus operator, mind you, because in modulus arithmetics a mod b
by definition evaluates to a non-negative value for any value of a
and any positive value of b
. In C++ the sign of the result of a % b
is implementation-defined if either of the arguments is negative. So, we would more appropriately name the %
operator the remainder operator.
C ++有%运算符,偶尔会误导性地命名为“模数”运算符。特别是STL在
That said, if you truly want the mathematical modulus operator then you can define a function to do just that:
也就是说,如果你真的想要数学模数运算符,那么你可以定义一个函数来做到这一点:
template<typename V>
V mod(const V& a, const V& b)
{
return (a % b + b) % b;
}
So long as b
is a positive value a call to the above function will yield a non-negative result.
只要b是正值,对上述函数的调用将产生非负结果。
#5
2
Using the modulus %
operator :
使用模数%运算符:
int modulus_a_b = a % b;
#6
0
if you use double variable, you should use;
如果你使用双变量,你应该使用;
double x;
double y;
double result = fmod(x, y);