c언어교양 20160405

#include <stdio.h>
#include <stdlib.h>

main()
{
      int n1,n2;
      char op;
     
      printf("두 수 입력?\n");
      scanf("%d%d",&n1,&n2);
      fflush(stdin); // getchar();
      printf("연산자?");
      scanf("%c",&op);
     
      switch(op)
      {
             case '+':printf("%d + %d = %d\n",n1,n2,n1+n2);break;
             case '-':printf("%d - %d = %d\n",n1,n2,n1-n2);break;
             case '*':printf("%d * %d = %d\n",n1,n2,n1*n2);break;
             case '/':printf("%d / %d = %d\n",n1,n2,n1/n2);break;
             case '%':printf("%d %% %d = %d\n",n1,n2,n1%n2);break;
             default : printf("잘못된 연산자\n");
             }       
     
      system("pause");
     
      }

 

학점

 

#include <stdio.h>
#include <stdlib.h>

main()
{
      int p,;
      char grade;
     
      printf("점수 입력?\n");
      scanf("%d",&p);
     
      switch(p/10)
      {
             case 9 : case 10: grade = 'A';break;
             case 8 :grade = 'B';break;
             case 7 :grade = 'C';break;
             case 6 :grade = 'D';break;
             default : grade = 'F';break;
            
             }
             printf("점수 %d 는 %c \n",p,grade);  
     
      system("pause");

 

 

구구단

 

#include <stdio.h>
#include <stdlib.h>

main()
{
      int x,y;
      for(x=1; x<=9; x++)
      {
               for(y=1; y<=9; y++)
               printf("%dx%d=%d ",x,y,x*y);
               printf("\n");
              
               }
      system("pause");
     
      }