是的。
long只是long int的简写。“这是因为原则上long只是一个限定符（例如，它还可以用于延长double数据类型）
C++ ISO标准的7.1.5.2一节中提供了等效类型说明符的表：

的数据

C99标准的§6.7.2给出了以下类型列表（这只是摘录）：

• short、signed short、short int或signed short int
• unsigned short或unsigned short int
• int、signed或signed int
• unsigned或unsigned int
• long、signed long、long int或signed long int
• unsigned long或unsigned long int
• long long、signed long long、long long int或signed long long int
• unsigned long long或unsigned long long int

并附加以下一点：
(5)每个逗号分隔的集合指定相同的类型，除了对于位字段，说明符int是指定与signed int相同的类型还是与unsigned int相同的类型是实现定义的。

• 是 *. unsigned，signed，short，long，long long都是XXX int的简单类型说明符。

参见标准中的 7.1说明符[dcl.spec]：
3 [注意：由于signed、unsigned、long和short默认隐含int，出现在其中一个说明符之后的类型名称被视为正在（重新）声明的名称。[示例：
void h(unsigned Pc); // void h(unsigned int)个
void k(unsigned int Pc); // void k(unsigned int)个

• 结束示例] -结束注解]
  7.1.6.2简单类型说明符[dcl.type.simple]*

Table 10 — simple-type-specifiers and the types they specify

    Specifier(s)            | Type
    ------------------------+---------------------------------
    type-name               | the type named
    simple-template-id      | the type as defined in 14.2
    char                    | “char”
    unsigned char           | “unsigned char”
    signed char             | “signed char”
    char16_t                | “char16_t”
    char32_t                | “char32_t”
    bool                    | “bool” 
    unsigned                | “unsigned int”
    unsigned int            | “unsigned int”
    signed                  | “int”
    signed int              | “int”
    int                     | “int”
    unsigned short int      | “unsigned short int”
    unsigned short          | “unsigned short int”
    unsigned long int       | “unsigned long int”
    unsigned long           | “unsigned long int”
    unsigned long long int  | “unsigned long long int”
    unsigned long long      | “unsigned long long int”
    signed long int         | “long int”

字符串

unsigned long int是正确的类型定义，但是int可以忽略。

是的，它们是一样的。说unsigned long int只是明确地声明它是一个int。
您始终可以通过sizeof(unsigned long int)和sizeof(unsigned long)查看类型的大小
希望这对你有帮助。