C++ difference between [ ] and ( ) when declaring an array -

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can tell me difference between these 2 lines of c++ code?

int *p = new int (7);

and 

int *p = new int [7];

i can't spot difference except in first 1 put number 7 in p[0] , there other difference? , in case when there char instead of int happen?

thanks in advance.

one array of 7 items

new int [7]

the other initialising pointer int value of 7


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