Given the two C$++$ code snippets below, in which situation their output will certainly not be the same? $...$ a$++$; while $($a $<5)\{$ std::cout $<<$ a $+$ b; a$++$; $\}...$ do $\{$ a$++$; std::cout $<<$ a $+$ b; $\}$ while $($a $<4)$; if a is greater than $3.$ if a is smaller than $4.$ if a is smaller than b$.$ if a is greater than b$.$