c++中printf函数的参数传递与解析

?C++?,printf????C???????,????????printf????????????????:

1. ????:printf?????????????????(format string),?????????????????????????????????(placeholder)?????

#include
using namespace std;

int main() {
    int a = 5;
    float b = 7.5;
    const char* s = "Hello, World!";

    printf("Integer: %d, Float: %.2f, String: %s\n", a, b, s);
    return 0;
}

2. ????:???????????????????????????????????????????:

• %d:??(int)
• %f:???(float/double)
• %s:???(const char*)
• %c:??(char)
• %x/%X:??????(int)
• %o:?????(int)
• %e/%E:???????????(float/double)
• %g/%G:??????????????(float/double)

????????????,??:

• -:???
• +:?????
• 0:?????
• ??:??????,??????
• .:?????????
• *:????????????

#include
using namespace std;

int main() {
    int a = -123;
    float b = 3.14159;

    printf("Left aligned: %-10d\n", a);
    printf("Always show sign: %+d\n", a);
    printf("Leading zeros: d\n", a);
    printf("Space for positive numbers: % d\n", a);
    printf("Fixed decimal places: %.2f\n", b);
    printf("Variable width and precision: %*.*f\n", 8, 2, b);
    return 0;
}

??:?C++?,?????std::cout???????,???????????????????printf???C++?????,??????????