在乌班图20 的版本上

下面是C语言编程的十六进制转十进制代码：

#include <stdio.h>

int main() {
    char hex[20];
    int decimal, place;

    printf("Enter any hexadecimal number: ");
    scanf("%s", hex);

    decimal = 0, place = 1;

    for (int i = strlen(hex) - 1; i >= 0; i--) {
        int hexDigit;

        if (hex[i] >= '0' && hex[i] <= '9') {
            hexDigit = hex[i] - '0';
        } else if (hex[i] >= 'a' && hex[i] <= 'f') {
            hexDigit = hex[i] - 'a' + 10;
        } else if (hex[i] >= 'A' && hex[i] <= 'F') {
            hexDigit = hex[i] - 'A' + 10;
        } else {
            printf("Invalid hex input!\n");
            return 0;
        }

        decimal += hexDigit * place;
        place *= 16;
    }

    printf("The decimal value is: %d\n", decimal);
}