一切正常，除了当我将选择3设置为set dosa时，它将该输入视为无效，尽管它不是

Question

这些是代码的一些变体，所有变体的输出都是相同的。我尝试过使用指针，并通过定义函数 caseInsensitiveComparision 以及逻辑中的一些细微更改，在由所有更改组合组成的所有变体中，都会产生相同的输出 -

输入选择数量（最多 5 个）：3 输入选择 1：idli idli 价格：Rs15/- 输入选择2：茶 茶价：Rs15/- 输入选择 3：设置剂量 在菜单中找不到选择集。 包括 GST 在内的应付账单总额为：Rs30/-

 #include <stdio.h>
#include <string.h>

const char items[5][20] = {"TEA", "COFFEE", "IDLI", "SET DOSA", "MASALA DOSA"};
int prices[5] = {15, 20, 15, 30, 40};  // Predefined prices

int findItemIndex(const char *selection) {
    for (int i = 0; i < 5; i++) {
        if (strcasecmp(selection, items[i]) == 0) {
            return i;
        }
    }
    return -1;  // Return -1 if not found
}

int main() {
    char selections[5][20];  // User inputs for selections
    int numSelections, totalBill = 0;
    
    printf("Enter the number of selections (up to 5): ");
    scanf("%d", &numSelections);

    for (int i = 0; i < numSelections; i++) {
        printf("Enter selection %d: ", i + 1);
        scanf("%19s", selections[i]);

        int index = findItemIndex(selections[i]);
        if (index != -1) {
            printf("Price for %s: Rs%d/-\n", selections[i], prices[index]);
            totalBill += prices[index];
        } else {
            printf("Selection %s not found in the menu.\n", selections[i]);
        }
    }

    if (totalBill == 0) {
        printf("No valid selections found.\n");
    } else {
        printf("The total bill payable including GST is: Rs%d/-\n", totalBill);
    }

    return 0;
}

这是另一种变体：

#include <stdio.h>

int caseInsensitiveCompare(const char str1[], const char str2[]) {
    int i = 0;
    while (str1[i] && str2[i]) {
        if (tolower((unsigned char)str1[i]) != tolower((unsigned char)str2[i])) {
            return 0;  // Not equal
        }
        i++;
    }
    return (str1[i] == '\0' && str2[i] == '\0');
}

const char items[5][20] = {"TEA", "COFFEE", "IDLI", "SET DOSA", "MASALA DOSA"};
int prices[5] = {15, 20, 15, 30, 40};  // Predefined prices

int findItemIndex(const char selection[]) {
    for (int i = 0; i < 5; i++) {
        if (caseInsensitiveCompare(selection, items[i])) {
            return i;
        }
    }
    return -1;  // Return -1 if not found
}

int main() {
    char selections[5][20];  // User inputs for selections
    int numSelections, totalBill = 0;
    
    printf("Enter the number of selections (up to 5): ");
    scanf("%d", &numSelections);

    for (int i = 0; i < numSelections; i++) {
        printf("Enter selection %d: ", i + 1);
        scanf("%19s", selections[i]);

        int index = findItemIndex(selections[i]);
        if (index != -1) {
            printf("Price for %s: Rs%d/-\n", items[index], prices[index]);
            totalBill += prices[index];
        } else {
            printf("Selection %s not found in the menu.\n", selections[i]);
        }
    }

    if (totalBill == 0) {
        printf("No valid selections found.\n");
    } else {
        totalBill += totalBill * 0.18;
        printf("The total bill payable including GST is: Rs%d/-\n", totalBill);
    }

    return 0;
}

Answer 1

我注意到您的其中一件商品有一个空格：

"MASALA DOSA"

。但是您将

%19s

与

scanf

一起使用。这将在第一个空格处停止读取，这意味着用户输入

MASALA DOSA

会将

MASALA

读入变量中。这显然不会匹配数组中的任何值。

要读取 19 个或更少的字符直至换行，请使用

%19[^\n]

作为格式说明符。