运行两次，倒数第三个位置没变，结果却变了？

#include <stdio.h>

int main()

{

    double money =12      ; 

    double cost =11.5       ;  

    printf("小编能不能打车回家呢："); 

    printf("%c\n",money>=cost?'y':'n');

    printf("%c\n",(money>=cost)?'y':'n');

    printf("%c\n",(money>cost)||(money=cost)?'y':'n');

    printf("%c\n",(money=cost)||(money>cost)?'y':'n');

    printf("%c\n",((money>cost)||(money=cost))?'y':'n');

    printf("%c\n",(money>cost)&&(money=cost)?'y':'n');

    printf("%c\n",(money=cost)&&(money>cost)?'y':'n');

    printf("%c\n",((money>cost)&&(money=cost))?'y':'n');

    return 0;

}

#include <stdio.h>

int main()

{

    double money =12      ; 

    double cost =11.5       ;  

    printf("小编能不能打车回家呢："); 

    printf("%c\n",money>=cost?'y':'n');

    printf("%c\n",(money>=cost)?'y':'n');

    printf("%c\n",(money>cost)||(money=cost)?'y':'n');

    printf("%c\n",((money>cost)||(money=cost))?'y':'n');

    printf("%c\n",(money>cost)&&(money=cost)?'y':'n');

    printf("%c\n",(money=cost)&&(money>cost)?'y':'n');

    printf("%c\n",((money>cost)&&(money=cost))?'y':'n');

    return 0;

}