Too easy function

Let a power function $p(x)$ be represented as $y=x^{n}$ , and a constant function $c(x)$ be represented as $y=mx + b$ . Now for certain value of $(n,m,b)$ ; $p(x)=c(x)$ ,for every $'x'$ in the interval $-\infty < x < \infty$ .Then find $n+m+b$