62 lines
1.5 KiB
C++
62 lines
1.5 KiB
C++
#include <iostream>
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#include <cstdlib>
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#include <iostream>
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#include <cstdlib>
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class TRandom {
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private:
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unsigned long seed;
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public:
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TRandom(unsigned long s) : seed(s) {}
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unsigned char NextByte() {
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seed = seed * 1103515245 + 12345;
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return static_cast<unsigned char>((seed / 65536) % 256);
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}
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};
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void Coder(unsigned char data[], int len, unsigned long key) {
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TRandom rand(key);
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for (int i = 0; i < len; ++i) {
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data[i] ^= rand.NextByte();
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}
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}
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void Coder(unsigned char data[], int len, TRandom& rand, unsigned long key) {
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for (int i = 0; i < len; ++i) {
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data[i] ^= rand.NextByte();
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}
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}
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class Crypter {
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private:
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TRandom rand;
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public:
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Crypter(unsigned long seed) : rand(seed) {}
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void Process(unsigned char data[], int len) {
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for (int i = 0; i < len; ++i) {
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data[i] ^= rand.NextByte();
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}
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}
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};
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void Test() {
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unsigned char msg[] = "Hello World";
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int len = sizeof(msg);
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unsigned long key = 12345;
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std::cout << "Original: " << msg << std::endl;
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Coder(msg, len, key);
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std::cout << "Encrypted: "; for (int i = 0; i < len; ++i) std::cout << msg[i]; std::cout << std::endl;
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Coder(msg, len, key);
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std::cout << "Decrypted: " << msg << std::endl;
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}
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int main(){
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Test();
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return 0;
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}
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// 问题3：将 rand 改为 TRandom rand（传值），会丢失原状态，重复初始化种子，不可行
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// 问题4：改为 const TRandom& rand，不行，因为 NextByte 改变对象状态，不能用于 const
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