Different methods of swap numbers without using third variable

int a=4,b=5;

1st Method:
b=(a+b)-(a=b);

2nd Method:
a^=b^=a^=b;

3rd Method:
a=a+b;
b=a-b;
a=a-b;

4th Method:
a=a*b;
b=a/b;
a=a/b;

5th Method:
a=b-~a-1;
b=a+~b+1;
a=a+~b+1;