vernam

vernam.c

#include <stdio.h>

int main(){
	int M,m;
	int ch,k,r;
	ch=getchar();
	//ascii >> A=65,a=97 e Z=90,z=122
	for (M=65, m=97;(M<=90) && (m<=122);M++, m++){
		while ((ch=getchar()) != EOF){
			r=rand()%26;
			if ((ch>='A') && (ch<='Z')){
				k=ch+r;
				putchar((ch-'A'+k)%26+'A');
			}
			else if ((ch>='a') && (ch<='z')){
				k=ch+r;
				putchar((ch-'a'+k)%26+'a');
			}
			
		}
	}
}