array_sample_merge_sort.texy

void print_wordarray(Word a[], int n){
    int i;
    printword("--------------------");
    for (i=0; i<n; i=i+1){
        printword(a[i]);
    }
}

int merge(Word a[], int l, int m, int r){
    int n1;
    int n2;
    Word buf[];

    int i;

    buf = [" "," "," "," "," "," "," "," "," "," "," "," "," "];

    n1=l;
    n2 = m+1;
    i=l;

    for (i=l;n1<=m&&n2<=r;i=i+1) {
        if(strcmp(a[n1], a[n2])<=0) {
            buf@[i] = a[n1];
            n1= n1+1;
        }
        else {
            buf@[i] = a[n2];
            n2= n2+1;
        }
    }

    while(n1<=m){
        buf@[i]= a[n1];
        i=i+1;
        n1= n1+1;
    }
    
    while(n2<=r){
        buf@[i]= a[n2];
        i=i+1;
        n2= n2+1;
    }
    for (i=l;i<=r;i=i+1){
        a@[i]=buf[i];
    }
    return 0;
}

int merge_sort(Word a[], int l, int r){
    int m;
    if(l <r){
        m = (l+r)/2;
        merge_sort(a, l, m);
        merge_sort(a, m+1, r);        
        merge(a, l, m, r);
    }
    return 0;
}

int main() {
    Word names[];
    int i;
    
    names = ["Stephen","Thomas","Dennis","Dop","Able","Bob","Celtic","Ethen","Mike"];

    printword("Before sorted:");
    print_wordarray(names, 9);
    printword(" ");
    merge_sort(names,0,8);
    
    printword("After merge sort:");
    print_wordarray(names, 9);
    return 0;
}