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

int testcase,len,p,q,a,b,time;
char str[1000]="";

int main(){
    scanf_s("%d", &testcase);

    while(testcase){
        len=0;
        time=0;
        p,q,a,b=0;
        int i=0;

        scanf_s("%d", &len);
        scanf_s("%s", str, len+1);
        scanf_s("%d %d", &p, &q);

        if(p<q){
            a=p, b=q;
        }
        else{
            a=q, b=p;
        }

        i=0;

        while(i <= len-i-1) {

            if(str[i]=='?' && str[len-i-1]=='?'){
                if(len-i-1 != i)
                    time += 2*a;
                else
                    time+=a;
            }

            else if(str[i]=='?'&& str[len-i-1]=='a')
                time+=a;
            else if(str[i]=='?'&& str[len-i-1]=='b')
                time+=b;
            else if(str[i]=='a' && str[len-i-1]=='?')
                time += a;
            else if(str[i]=='b'&& str[len-i-1]=='?')
                time+=b;

            i++;
        }

        printf("%d\n", time);
        testcase--;
    }

    return 0;
}

----------------------------------------------------------------                         
<<컴파일오류>>

submission.cpp:8:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &testcase);
                        ^
submission.cpp:16:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &len);
                    ^
submission.cpp:17:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%s", str);

-------------------------------------------------------------
   이렇게 오류가 났습니다
   근데 무슨의미인지 잘 모르겠네요..ㅠㅠ
   비쥬얼스튜디오 2013에서는 잘 돌아가요.. 오류없이 !!