Stupid link list

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


typedef struct node
{
    char c;
    struct node *next;

}*NodePtr;



void printlist(NodePtr list)
{
    NodePtr temp = list;
    do{
        printf("%c", temp->c);
        temp=temp->next;
    }while(temp!=NULL);
    printf("\n");
}


NodePtr newNode(char str)
{
    NodePtr np = (NodePtr) malloc(sizeof (NodePtr));
    np -> c = str;
    np -> next = NULL;
    return np;
}

void replace(NodePtr list, char c1, char c2)
{
    while(list){
        if(list->c == c1 )
        list->c = c2;

        list=list->next;
    }
}

NodePtr removenode(NodePtr list, char c3)
{
    NodePtr temp =list, prev = NULL;
    while(temp!=NULL){
        if(temp->c == c3 )
    {
        if(list == temp ){
            list=temp->next;
            free(temp);
            temp=list;
        }else
        {
            prev->next= temp->next;
            free(temp);
            temp= prev->next;
        }
    }
        else
        {
            prev = temp;
            temp= temp->next;
        }
    }
    //printlist(list);
    return list;
}
void toUpper(NodePtr list)
{
    while(list)
    {
        list->c = toupper(list->c);
        list = list->next;
    }
}
void toLower(NodePtr list)
{
    while(list)
    {
        list->c = tolower(list->c);
        list = list->next;
    }
}

NodePtr alfaSort(NodePtr list)
{
    NodePtr bfrFirst=NULL, First=NULL, prev = NULL, temp =list;
    char FirstChar = '~'; //karena memiliki nilai terbesar di ASCII Table

    if(list->next==NULL)
    return list;

    while(temp)
    {
        if(temp->c < FirstChar){
            FirstChar = temp->c;
            First = temp;
            if(prev !=NULL)
                bfrFirst= prev;
        }
        prev= temp;
        temp= temp->next;
    }

    if(bfrFirst!=NULL)
        bfrFirst->next= First->next;
    if(First!=list)
        First->next = list;

    list=First;
    list->next = alfaSort(list->next);

    return list;
}

int compare(NodePtr list, NodePtr cmp)
{
    NodePtr temp = list;
    NodePtr Banding = cmp;
    int tanda = 0;
    while(temp){
    //  printf("0");
        if(temp->c == Banding->c)
        {
            tanda=1;
            if(Banding->next== NULL) return 1;
            else {
            temp=temp->next;
            Banding=Banding->next;
        //      printf("1");
            }
        //  printf("2");
        } else temp = temp->next;
    }
    if (tanda == 0) return 0;
}
int main(){
    char str[100],c1,c2;
    int n=0;
    NodePtr head =NULL, tail, temp, sorted;
    printf("masukkan Kalimat: ");
    gets(str);

    while(str[n]!='\0')
    {
        temp= newNode(str[n]);
        if(head==NULL)  head=temp;
        else
        tail->next = temp;
        tail = temp;
        n++;
    }
    //printlist(head);
    // -------------------fungsi E -----------------------
    printf("Kalimat yang akan dibandingkan: ");
    gets(str);
    NodePtr cmp=NULL, ctemp,ctail;
    n=0;
    while(str[n]!='\0')
    {
        ctemp= newNode(str[n]);
        if(cmp==NULL) cmp=ctemp;
        else
        ctail->next = ctemp;
        ctail = ctemp;
        n++;
    }
    if(compare(head, cmp)==1) printf("Sama\n");
    else printf("Beda\n");
    // -------------------fungsi A-----------------------
    printf("huruf yang ingin di ganti dan penggantinya: ");
    scanf("%c %c",&c1, &c2);
    replace(head,c1,c2);

    printlist(head);
    getchar();
    // -------------------fungsi B -----------------------
    printf("huruf yang ingin dihapus: ");
    scanf("%c",&c1);
    head = remove(head,c1);
    printlist(head);
    // -------------------fungsi C -----------------------
    printf("Huruf Kapitalis: ");
    toUpper(head);
    printlist(head);
    // -------------------fungsi D -----------------------
    printf("Huruf yang Terurut: ");
    sorted = head;
    toLower(sorted);
    alfaSort(sorted);
    //getchar();
    printlist(sorted);

    //printlist(cmp);
}