凯撒加密方法将文件内容进行加密

Question

 

Answer 1

#include <iostream>
#include <fstream>
using namespace std;
 
int main()
{
	ifstream iFile("D:\\测试1.txt");   //建立输入文件流对象
	iFile.seekg(0, ios::end);		
	int nFileLen = iFile.tellg();
	iFile.seekg(0, ios::beg);
	char *str = new char[nFileLen + 1];
	iFile.read(str, nFileLen);
	iFile.close();
	str[nFileLen] = 0;
	int nCaesar = 5;   //设置偏移量
	int n = 0;         //记录回车数目
	for (int i = 0; i < nFileLen; i++)
	{
		if ((str[i] >= 'a') && (str[i] <= 'z'))
		{
			str[i] += nCaesar;
			if (str[i] > 'z')
				str[i] -= 26;
		}
		else if ((str[i] >= 'A') && (str[i] <= 'Z'))
		{
			str[i] += nCaesar;
			if (str[i] > 'Z')
				str[i] -= 26;
		}
		else if (str[i] == '\n')
			n++;
	}
	ofstream oFile("D:\\测试2.txt");
	oFile.write(str, nFileLen - n);
	oFile.close();
	delete[] str;
	str = nullptr;
	return 0;
} 

这里有个凯撒加密方法例子参考一下！