实验啊

#include <stdio.h>
#include <stdio.h>
int main()
{
 int a,b,sum;
 a=123;
 b=456;
    sum=a+b;
 printf("sum is %d\n",sum);
  return 0;
}

#include <stdio.h>
int main()
{ char c1,c2
  c1=97;
  c2=98;
  printf("c1=%c,c2=%c\n",c1,c2);
  printf("c1=%d,c2=%d\n",c1,c2);
  return 0;
}

#include <stdio.h>
int main()
{ char c1,c2
  c1=197;
  c2=198;
  printf("c1=%c,c2=%c\n",c1,c2);
  printf("c1=%d,c2=%d\n",c1,c2);
  return 0;
}

#include <stdio.h> #include <math.h>

int main(){     double x,y,z;     scanf("%lf%lf",&x,&y);     z = x + 1/fabs(y);     printf("%15.6f\n",z);  printf("%d\n",(int)z);  printf("%e\n",z);  return 0 ; }