netfee.cpp

计算概论阅读材料

#define DAYCOST 0.000007
#define NIGHTCOST 0.0000035
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>

void count(FILE *fpin,FILE *fpout,FILE *fpindex);
void main(int argc,char *argv[])
{
	if(argc!=3) {
		printf("Usage: netfee infile outfile\n");
		exit(0);
	}
	FILE *fpin,*fpout,*fpindex;
	if((fpin=fopen(argv[1],"rt"))==NULL) {
		printf("%s: file not found\n",argv[1]);
		exit(0);
	}
	if((fpout=fopen(argv[2],"rt"))!=NULL)
	{
		printf("%s: file is exist,overwrite(y/n)?\n",argv[2]);
		if(tolower(getchar())!='y')
			exit(0);
		else
			fclose(fpout);
	}
	if((fpout=fopen(argv[2],"w+t"))==NULL) {
		printf("%s: write file failed\n",argv[2]);
		exit(0);
	}
	if((fpindex=fopen("feeindex.txt","rt"))==NULL) {
		printf("can't get index file\n");
		exit(0);
	}
	count(fpin,fpout,fpindex);
	fclose(fpout);
	fclose(fpin);
	fclose(fpindex);
}
void count(FILE *fpin,FILE *fpout,FILE *fpindex)
{
	char linebuf[80],indexbuf[80];
	char IPaddress[80],IPorGroup[80];
	long inoctets,outoctets;
	float total=0;
	int day;
	float daycosts,nightcosts;
	long dayoctets,nightoctets;
	while(fgets(indexbuf,80,fpindex)!=NULL){
		daycosts=0;nightcosts=0;
		dayoctets=0;nightoctets=0;
		if(sscanf(indexbuf,"%s",IPorGroup)==EOF)
			continue;
		if(IPorGroup[0]!='1'){
			fprintf(fpout,"           Total:  %8.2f\n",total);
			total=0;
			fprintf(fpout,"%s",indexbuf);
			continue;
		}
		fseek(fpin,0,SEEK_SET);
		while(fgets(linebuf,80,fpin)!=NULL){
			if(strstr(linebuf,"DAY")) {
				day=1;
				continue;
			}
			else if(strstr(linebuf,"NIGHT")) {
				day=0;
				continue;
			}
			sscanf(linebuf,"%s %ld %ld",IPaddress,&outoctets,&inoctets);
			if(strcmp(IPaddress,IPorGroup))
				continue;
			if(day){
				dayoctets=inoctets;
				daycosts=inoctets*DAYCOST;
				total+=daycosts;
			}
			else{
				nightoctets=inoctets;
				nightcosts=inoctets*NIGHTCOST;
				total+=nightcosts;
			}
		}
		fprintf(fpout,"%s ",indexbuf);
		fprintf(fpout,"               %10.2f %8ld %8ld\n",daycosts+nightcosts,dayoctets,nightoctets);
	}
}