#include<stdio.h>

int main(void)
{
           int i=0,num1,num2,qq_ts,b=0;
           char a;
           printf("최범석 해킹1B\n");
           for(;b<1;)
           {
                         for(i=0;i<45;i++)
                                    printf("*");
                         printf("\n");
                         printf("A:add, S:subtract, M:multiply, D:divide, Q:quit\n");
                         for(i=0;i<45;i++)
                                    printf("*");
                         printf("\n");
                         printf("연산을 선택하시오 : ");
                         scanf("%c",&a);
                         if(a=='A'||a=='a')
                                    qq_ts=1;
                         else if(a=='S'||a=='s')
                                    qq_ts=1;
                         else if(a=='M'||a=='m')
                                    qq_ts=1;
                         else if(a=='D'||a=='d')
                                    qq_ts=1;
                         else
                                    qq_ts=0;
                         if(qq_ts==1)
                         {
                                    printf("두수를 공백으로 분리하여 입력하시오 : ");
                                    scanf("%d%d",&num1,&num2);
                         }
                         if(a=='A'||a=='a')
                                    printf("연산결과는 %d입니다.\n",num1+num2);
                         else if(a=='S'||a=='s')
                                    printf("연산결과는 %d입니다.\n",num1-num2);
                         else if(a=='M'||a=='m')
                                    printf("연산결과는 %d입니다.\n",num1*num2);
                         else if(a=='D'||a=='d')
                                    printf("연산결과는 %f입니다.\n",(float)num1/num2);
                         else if(a=='Q'||a=='q')
                                    b=1;
           }
           qq_ts=0;
           printf("프로그램을 종료합니다");
           return 0;
}


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