cwshu · November 18, 2018 06:32
diff --git a/foo.c b/foo.c
 int foo(int a, int b)
 {
    return a+b;                                                                                                          
 }
diff --git a/foo.h b/foo.h
 #ifdef __cplusplus
 extern "C" {
 #endif // __cplusplus

 int foo(int a, int b);

 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus

 #ifdef __cplusplus
 int foo(int a, int b = 10);
 #endif // __cplusplus
diff --git a/main.cpp b/main.cpp
 #include <cstdio>
 #include "foo.h"
                                                                                                                         
 int main(int argc, char *argv[]){
    printf("%d, %d\n", foo(1, 2), foo(20));
    return 0;
 }