为什么这个程序会崩溃？（文件写入读出）

Question

程序如下：
#include
#include
#include"string"

int save_ps() ;
int load_ps() ;

struct Car
{
std::string maker ;
float price ;
};
struct Citizen
{
std::string name ;
float deposite ;
Car *car ;
};

int main()
{
save_ps() ;
//load_ps() ;

return 0 ;

}
int save_ps()
{
const char* filename = "inputdataps.txt" ;
FILE* fp = fopen(filename,"wb") ;

if ( fp == NULL )
{
    std::cerr << "Can not open the file ! " << std::endl ;
    return -1 ;
}

Car *car = (Car *) malloc (sizeof(Car)) ;
car->maker = "BMW" ;
car->price = 2000 ;

Citizen man = { "feng" , 200000  } ;
man.car = car ;

fwrite(&man.name,1,sizeof(man.name),fp) ;
fwrite(&man.deposite,1,sizeof(man.deposite),fp);

if ( man.car != NULL )
{
    fwrite ( "Y" , 1 , 1 , fp ) ;
    fwrite ( &man.car->maker , 1 , sizeof( man.car->maker ) , fp ) ;
    fwrite ( &man.car->price , 1 , sizeof( man.car->price ) , fp ) ;
}
else
{
    fwrite ( "N" , 1 , 1 , fp ) ;
}

fclose(fp) ;

return 0 ;

}

int load_ps()
{
const char* filename = "save_ps.txt" ;
FILE* fp = fopen(filename,"rb") ;

if ( fp == NULL )
{
    std::cerr << "Can not open the file ! " << std::endl ;
    return -1 ;
}

Citizen man ;
fread(&man.name , 1 , sizeof(man.name) , fp) ;
fread(&man.deposite , 1 , sizeof(man.deposite) , fp) ;

char has_car_YN = 'N' ;
fread( &has_car_YN , 1 , sizeof(has_car_YN) , fp ) ;

if ( has_car_YN == 'Y' )
{
    Car *car = (Car*) malloc(sizeof(Car)) ;

    fread(&car->maker,1,sizeof(car->maker),fp) ;
    fread(&car->price,1,sizeof(car->price),fp) ;
}
else
{
    man.car = NULL ;
}

fclose(fp);

}

主要的问题好像出现在save_ps()里边，只是运行了这个函数就崩了...
各位大神，帮小弟分析下好吗？

Answer 1

http://www.zhihu.com/question/36501005