Question

我是新来的，所以请在解释我的问题时请耐心等待

我正在尝试创建一个函数，其中查找销售额最多的日期。我这样做是通过读取包含以下内容的文件中的数据来实现的：

date, item, count

我正在使用链接列表来过滤链表中的所有销售结构（按日期排序）

这是我的结构：

typedef struct sales {
    int amount;
    char *date;
    struct stockItem *item;
    struct sales *next;
} sales;

以下是查找哪一天销售额最高的代码：

sales *sFirstNode = NULL;
sales *sLastNode = NULL;

int findHighestVolumeSales() {
        char *previousDate = NULL;
        struct sales *tmpPtr = sFirstNode;
        struct sales *tmpNxt = sFirstNode->next;
        char *currentDate = tmpPtr->date;
        int tmp=0;
        int mostSales;
        while(tmpNxt != NULL){
               while(tmpNxt != tmpPtr){
                        if(currentDate == previousDate){
                                tmp = tmpPtr->amount + tmp;
                         }
                         else{
                                tmp = tmpPtr->amount;
                         }
                         if(tmp > mostSales){
                            mostSales = tmp;
                            printf("%d\n", mostSales);
                         }
                        previousDate = tmpPtr->date;
                        tmpPtr = tmpPtr->next;
                }
                tmpPtr = sFirstNode;
                tmpNxt = tmpNxt->next;
        }
        printf("%d\n", mostSales);
        return mostSales;
    }

函数返回的值似乎是地址而不是mostSales本身。

我收到了：

价值很大，但没有这么大。我确定我的代码存在问题

编辑：

int findHighestVolumeSales() {
        char *previousDate = NULL;
        struct sales *tmpPtr = sFirstNode;
        struct sales *tmpNxt = sFirstNode->next;
        char *currentDate = NULL;
        int tmp=0;
        int mostSales =0;
        while(tmpNxt != NULL){
               currentDate = tmpPtr->date;
               while(tmpNxt != tmpPtr){
                       // printf("%d \n", mostSales);
                        if(currentDate == previousDate){
                                tmp = tmpPtr->amount + tmp;
                         }
                         else{
                                tmp = tmpPtr->amount;
                         }
                         if(tmp > mostSales){
                            mostSales = tmp;
                            printf("%d\n", mostSales);
                         }
                        previousDate = tmpPtr->date;
                        tmpPtr = tmpPtr->next;
                }
                tmpPtr = sFirstNode;
                tmpNxt = tmpNxt->next;
        }
        printf("%d\n", mostSales);
        return mostSales;// Place holder
    }

Answer 1

如果列表按日期顺序排列，您甚至不需要两个嵌套循环。另外，你忽略了初始化mostSales = 0;我继续测试日期指针的相等性，但是没有说它意味着什么。您可能需要修复日期的char数组。

int findHighestVolumeSales() {
    struct sales *tmpPtr = sFirstNode;
    char *currentDate;                          // perhaps array is needed
    char *mostDate;                             // ditto
    int tmp = 0;
    int mostSales = INT_MIN;                    // <<-- initialise !!!

    if(tmpPtr == NULL) {                        // the empty list
        return 0;
    }
    mostDate = currentDate = tmpPtr->date;      // perhaps strcpy()

    while(tmpPtr != NULL){                      // parse the list
        if(tmpPtr->date != currentDate) {       // perhaps strcmp(), don't know
            if(mostSales <= tmp) {              // check the max
                mostSales = tmp;                // stamp
                mostDate = currentDate;         // perhaps strcpy()
            }
            tmp = 0;                            // reset
            currentDate = tmpPtr->date;         // perhaps strcpy() to fixed array
        }
        tmp += tmpPtr->amount;                  // accumulate sales
        tmpPtr = tmpPtr->next;                  // advance
    }

    // check loose end
    if(mostSales <= tmp) {              // check the max
        mostSales = tmp;                // stamp
        mostDate = currentDate;         // perhaps strcpy()
    }

    printf("%d on %s\n", mostSales, mostDate);  // report
    return mostSales;
}

在链表C中找到最高销售量

1 个答案: