#include<math.h>
#include <stdio.h>
#define pi 3.1415926
void main()
{int a,h,l,i,sum;
 double d,k,m,b,s,y,z,f,c,e,x,x1,x2,x3,x4,g,n;
 sum=0;
 l=1550;
 k=1090.204;
 m=502.8;
 for(a=50;d<91;a++)
 {for(d=70;a<111;d++)
  {for(h=-20;h<201;h++)
   {for(i=1;i<28;i++)
    {f=(d*pi)/180;
     x=(i*pi)/180;
     x1=cos(f);
     x2=sin(f);
     x3=cos(f-x);
     x4=sin(f-x);
     g=(k-m)/2;
     b=sqrt((g-a*x1)*(g-a*x1)-(a*x2-h)*(a*x2-h));
     s=a*x3+sqrt(b*b-(a*x4-h)*(a*x4-h))-g;
     n=g-s;
     c=sqrt(h*h+n*n);
     y=(atan(h/n)+acos((a*a+h*h+n*n-b*b)/(2*a*c)))*180/pi;
     z=atan(1/((1/tan(x))-(k/l)))*180/pi;
     e=y-z;
     if(e<0.5&&e>-0.5)
     {sum=sum+i;
     printf("sum=%d\n",sum);}
     else
         sum=0;;}
     if(sum==351)
     {
    printf("h=%d\n",h);
    printf("d=%d\n",d);
    printf("a=%d\n",a);
    sum=0;}
       else
           sum=0;}
    }}
   printf("s=%lf\n",s);
   printf("y=%lf\n",y);
   printf("z=%lf\n",z);
   printf("b=%lf\n",b);
   }

你程序的第一个循环有问题，d未初始化，且数据类型int 和 double转换有问题。