my caesar

#include <stdio.h>
#include <cs50.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, string argv[])
{
if (argc != 2)
{return1;}
else
{
return 0;
}
int k = atoi(argv[1]);
printf(''Enter your plain text: '');
string p = GetString();
for ( int i = 0, n = strlen(p); i < n; i++)
{
char c[i];
c[i] = (  p[i] + k ) %26;
printf(''%c'', c[i]);
}
printf(''\n'');
}