cs210-ps1-part a-p2

#include <stdio.h>

char DNA[] = "ATCATCTC";
char *tptr;
int tcnt;
int len;

int process() {
    int found = 0;
    if (tptr == NULL) return 0;
    while (*tptr) {
        printf("*tptr first time come is: %c with ASCII %d\n", *tptr, *tptr);
        len++;
        if (*tptr == 'T') {
            printf("if, *tptr == 'T',  *tptr is: %c with ASCII %d\n", *tptr, *tptr);
            tcnt++;
            found = 1;
        } else {
            printf("else, Before *tptr = 'a' + (*tptr - 'A'),  *tptr is: %c with ASCII %d\n", *tptr, *tptr);
            *tptr = 'a' + (*tptr - 'A');
            printf("else, After *tptr = 'a' + (*tptr - 'A'),  *tptr now is: %c with ASCII %d\n", *tptr, *tptr);
        }
        tptr++;
        printf("!! after tptr++, it is %s  %c \n", tptr, *tptr);
        if (found) {
            printf(found ? "found is true\n" : "found is false\n");
            return 1;}
    }
    return 0;
}

int idx() {
    printf ("for idx():  DNA=%s  tptr=%s  tptr - DNA = %d\n", DNA, tptr, tptr-DNA);
    return (tptr) ? (tptr-DNA) : -1;
}

int main(int argc, char **argv) {
    tptr = DNA;
    tcnt = 0;
    len = 0;
    
    while (process()) printf("%d\n\n", idx());
    printf("DNA:%s Tptr:%s\n tcnt:%d  len:%d\n", DNA, tptr, tcnt, len);
    return 0;
}