sourpro.txt

这是用VC++6.0编写的一个简单的c语言的词法分析器

#include <stdio.h>
#define N 53.
typedef struct student
{
	int No;
	char Name[20];
	int Score[3];
	float Aver;
} STUD;
int main()
{
	STUD stu[N],temp;
	int i,j,loops,N_record=N;  
	FILE *fp;
        if((fp=fopen("stud","rb"))==NULL)
	{
		printf("Can't open the file!\n");
		return 0;
	}
	fread(&N_record,sizeof(int),1,fp);
	fread(stu,sizeof(STUD),N_record,fp);
	fclose(fp);
	for(loops=1;loops<N;loops++)
	  for(i=0;i<N-loops;i++)
		if(stu[i].Aver<stu[i+1].Aver)  
		{
			memcpy(&temp,&stu[i],sizeof(STUD));
			memcpy(&stu[i],&stu[i+1],sizeof(STUD));
			memcpy(&stu[i+1],&temp,sizeof(STUD));
		}
			
	if((fp=fopen("stu_sort","wb"))==NULL)
	{
		printf("Can't open the file !");
		return;
	}
	fwrite(&N_record,sizeof(int),1,fp);
	fwrite(stu,sizeof(STUD),N_record,fp);
	fclose(fp);
	fp=(FILE *)NULL;
	N_record=-1;
	memset(stu,0,sizeof(stu));
	fp=fopen("stu_sort","rb");
	fread(&N_record,sizeof(int),1,fp);
	fread(stu,sizeof(STUD),N_record,fp);
	fclose(fp);
	for(i=0;i<N;i++)
	{
		printf("%-4d  %-6s ",stu[i].No,stu[i].Name);
		for(j=0;j<3;j++)
			printf("%-6d\t",stu[i].Score[j]);
		printf("%-10f\n",stu[i].Aver);
	}
	return 0;
}