我想制作一个程序，产生一组序号，并把其中所有带4的序号全部去掉，但不知为什么总去不掉
源码如下，请高手指点指点，谢了
#include<stdio.h>
main()
{
      int ws;    //序号的位数
      int qs;    //序号的起始
      int js;    //序号的结束
      int n,m,i,j;            
      
      //输入参数
      
      printf("请输入序号的位（最少两位，最多四位）：");
      scanf("%d",&ws);
      printf("请输入起始号码：");
      scanf("%d",&qs);
      printf("请输入结束号码：");
      scanf("%d",&js);
      
      //生成序号数组
      
      n=(js-qs)+1;
      m=qs;
      int xh[n];  //序号数组
      for(i=0;i<n;i++)
      {
                      xh[i]=m;
                      m++;
      }
      
      //输出序号
      
      FILE *fp;
      fp=fopen("序号.txt","w+");
      for(i=0;i<n;i++)
      {
                      m=xh[i];
                      int x=1;
                      int y;
                      y=m;
                      if(y=4)
                      x++;
                      y=m/4;
                      if(y=4)
                      x++;
                      y=m/100;
                      if(y=4)
                      x++;
                      y=m/1000;
                      if(y=4)
                      x++;
                      y=m/10%10;
                      if(y=4)
                      x++;
                      y=m/100%10;
                      if(y=4)
                      x++;
                      if(x=1)
                      {
                             int z;
                             if(m<10)z=1;
                             else if(m<100)z=2;
                             else if(m<1000)z=3;
                             else if(m<10000)z=4;
                             switch(z)
                             {
                                  case 3:fputs("0",fp);break;
                                  case 2:fputs("00",fp);break;
                                  case 1:fputs("000",fp);break;
                                  default:return 0;
                             }
                             fprintf(fp,"%d\n",m);
                      }
      }
      fclose(fp);
}