题解 | #进制转换#

#include <math.h>
#include <stdio.h>
#include <string.h>
int main() {
    int sum = 0;
    char str[100] = {};
    scanf("%s",str);
    int len = strlen(str);
    for(int i = len-1; i>1; i--){
        if(str[i] >= '0' && str[i] <= '9'){
            sum+=((int)(str[i])-48)*pow(16,(len -1 -i));
        }else if (str[i] >= 'A' && str[i] <= 'Z') {
            sum+=((int)(str[i])-55)*pow(16,(len-1-i));
        }
    }
    printf("%d",sum);
}