What is the difference between Hashtable and HashMap ?

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The HashMap class is roughly equivalent to Hashtable, except that it is unsynchronized and permits nulls. A hashmap is not synchronized and faster than hashtable. The HashMap class is roughly equivalent to Hashtable, except that it is unsynchronized and permits nulls. HashMap does not guarantee that the order of the map will 
remain constant over time.

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main() { int c[ ]={2.8,3.4,4,6.7,5}; int j,p=c,q=c; for(j=0;j<5;j++) { printf(" %d ",c); ++q; } for(j=0;j<5;j++){ printf(" %d ",p); ++p; } }
main() { extern int i; i=20; printf("%d",i); }
main() { int i=-1,j=-1,k=0,l=2,a; a=i++&&j++&&k++\|\|l++; printf("%d %d %d %d %d",i,j,k,l,a); }
main() { int c=- -2; printf("c=%d",c); }
#define int char main() { int i=65; printf("sizeof(i)=%d",sizeof(i)); }
main() { int a=10; a=!a>14; Printf ("a=%d",a); }
#include main() { char s[]={'a','b','c','\n','c','\0'}; char p,str,str1; p=&s[3]; str=p; str1=s; printf("%d",++p + ++*str1-32); }
#include main() { int a[2][2][2] = {{10,2,3,4},{5,6,7,8}}; int p,q; p=&a[2][2][2]; q=*a; printf("%d----%d",p,*q); }