/* The Caesar cipher is a type of substitution cipher in which each letter in the plaintext is shifted to a certain number of places down the alphabet. For example, with a shift of 1, A would be replaced by B, B would become C, and so on. The method is named after Julius Caesar, who allegedly used it to communicate with his generals. For Example: Input: abcde 1 Output: Encrypted Message : bcdef Decrypted Message : zabcd Input: defend the east wall of the castle 1 Output: Encrypted Message : efgfoe uif fbtu xbmm pg uif dbtumf Decrypted Message : cdedmc sgd dzrs vzkk ne sgd bzrskd */ #include using namespace std; void Encrypt(char *,int); void Decrypt(char *,int); int main() { char msg[100]; int key=0; // cout<<"Enter Your Message:" ; cin.getline(msg,100); // cout<<"Enter key to Encrypt and Decrypt: "; cin>>key; cout<<"Entered Message : "<=65 && msg[i]<=90) || (msg[i]>=97 && msg[i]<=122)) { ect[i]=msg[i]+key; if(msg[i]>=97 && msg[i]<=122){ if(ect[i]>122) ect[i]=ect[i]-26; } else if(msg[i]>=65 && msg[i]<=90){ if(ect[i]>90) ect[i]=ect[i]-26; } } else ect[i]=msg[i]; } ect[i]='\0'; cout<<"\nEncrypted Message : "<=65 && msg[i]<=90) || (msg[i]>=97 && msg[i]<=122)) { dct[i]=msg[i]-key; if(msg[i]>=97 && msg[i]<=122){ if(dct[i]<97) dct[i]=dct[i]+26; } else if(msg[i]>=65 && msg[i]<=90){ if(dct[i]<65) dct[i]=dct[i]+26; } } else dct[i]=msg[i]; } dct[i]='\0'; cout<<"\nDecrypted Message : "<

CAESAR Cipher - 1 (C30)