Assume that the operators $+, -, \times$ are left associative and $^\hat{}$ is right associative. The order of precedence (from highest to lowest) is $ \ ^\hat{}, \times, +, -$. The postfix expression corresponding to the infix expression $a+ b \times c-d ^ \ \ \hat{}\ e^ \ \hat{} \ f$ is
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$abc\times+def \ \ \hat{}{} \ \ \ \hat{}-$
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$abc\times+de\ \ \hat{} \ \ f \ \ \hat{} \ \ -$
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$ab+c\times d-e \ \ \hat{} \ \ f \ \ \hat{}$
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$-+a\times bc \ \ \hat{} \ \ \ \hat{} \ \ def$