www.pudn.com > gudianmimaxue.rar > Cpp1.cpp

#include  
#include  
 
void main() 
{ 
	FILE *fi; 
	FILE *fo; 
	int ch,c,a,m,tc; 
	fi = fopen("license.txt","rb"); 
	fo = fopen("secret.txt","wb"); 
	int cc[256]={0}; 
	printf("请输入移位量：\n"); 
	scanf("%d",&m); 
	m=m%26; 
	while((ch=getc(fi))&&(ch!=EOF)) 
	{ 
		if(ch>=65&&ch<=90||ch>=97&&ch<=122) 
		{ 
			if (ch>='a') 
			{ 
				tc=((ch-'a'+m)%26)+'a'; 
				putc(tc,fo); 
			} 
			else 
			{ 
				tc=((ch-'A'+m)%26)+'A'; 
				putc(tc,fo); 
			} 
			cc[ch]++; 
			a++; 
		} 
		else putc(ch,fo); 
	} 
	printf("文件已加密，密文存储在secret.txt文件中\n"); 
	printf("原文中，各字母的个数为\n"); 
	printf("字母        个数\n"); 
	for(c=65;c<123;c++) 
	{	 
		if(c<=90||c>=97) 
		{ 
			printf("arc=%c        %d\n",c,cc[c]); 
		} 
	} 
 
	fclose(fi); 
 
}