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

void encode(char* input, char* output, char* matrix)
{
    while(*input)
    {
        size_t idx = strchr(matrix, *input++) - matrix;
        *output++ = '1' + idx / 6;
        *output++ = '1' + idx % 6;
    }
    *output = 0;
}

int main(void) {
    char matrix[]="ABCDEFGHIJKLMNOPRSTUVYZWX123456789?!-+* ";
    char input[50];
    
    printf("please enter an input");
    fgets(input, 50, stdin);
    *strchr(input, '\n') = '\0';
    
    size_t len = strlen(input);
    char output[2*len +1];
    
    encode(input, output, matrix);
    printf("\nEncoded String: %s\n", output);
    return 0;
}