IO day1

 

#include 
#include 
#include 
int main(int argc, const char *argv[])
{
	FILE *u=fopen("usr.txt","a+");
	if(NULL==u)
		perror("fopen");
	char a;
	char name[100];
	char pa[100];
	printf("是否注册账号 y or n：");
	scanf("%c",&a);
	if('y'==a)
	{
		scanf("%s %s",name,pa);
		fprintf(u,"%s %s\n",name,pa);
		int x=fclose(u);
		if(x<0)
		{
			perror("fclose");
		}
		FILE *u=fopen("usr.txt","a+");	
		if(NULL==u)
			perror("fopen");
	}
	printf("please enter 账号密码:\n");
	scanf("%s %s",name,pa);
	char arr[100];
	char brr[100];
	int sec=0;
	int w=0,q=0;
	while(1)
	{
	    sec=fscanf(u,"%s%s",arr,brr);
		if(EOF==sec)
			break;
		int m=strcmp(arr,name);
		int n=strcmp(brr,pa);
		if(m==0)
		{
			q++;
		}
		if(m==0&&n!=0)
		{
			w++;
		}
		if(m==0&&n==0)
		{
			printf("输出登录成功\n");
			break;
		}
	}
	if(q==0)
		printf("输出账户不存在\n");
	else if(w!=0)
		printf("密码错误\n");
    fclose(u);
	return 0;
}

#include 
#include 
#include 
int main(int argc, const char *argv[])
{
	FILE *fp=fopen("1.txt","r+");
	FILE *lp=fopen("2.txt","w+");
	if(NULL==lp&&NULL==fp)
		perror("fopen");
	else
		printf("success\n");
	int sec=0;
	int count =0;
	while(1)
	{
		int c=fgetc(fp);
		if(c==10)
			count++;
		if(EOF==c)
			break;
		sec++;
		fputc(c,lp);
	}
	printf("有%d个字节\n",sec);
	printf("有%d行\n",count);
	return 0;
}