### Book chapter

## Integer Conic Function Minimization Based on the Comparison Oracle

Let f:R^n→R be a conic function and x_0∈R^n. In this note, we show that the shallow separation oracle for the set K={x∈R^n:f(x)≤f(x_0)} can be polynomially reduced to the comparison oracle of the function *f*. Combining these results with known results of D. Dadush et al., we give an algorithm with (O(n))^n*logR calls to the comparison oracle for checking the non-emptiness of the set K∩Z^n, where *K* is included to the Euclidean ball of a radius *R*. Additionally, we give a randomized algorithm with the expected oracle complexity (O(n))^n*logR for the problem to find an integral vector that minimizes values of *f* on an Euclidean ball of a radius *R*. It is known that the classes of convex, strictly quasiconvex functions, and quasiconvex polynomials are included into the class of conic functions. Since any system of conic functions can be represented by a single conic function, the last facts give us an opportunity to check the feasibility of any system of convex, strictly quasiconvex functions, and quasiconvex polynomials by an algorithm with (O(n))^n*logR calls to the comparison oracle of the functions. It is also possible to solve a constraint minimization problem with the considered classes of functions by a randomized algorithm with (O(n))^n*logR expected oracle calls.Let f:R^n→R be a conic function and x_0∈R^n. In this note, we show that the shallow separation oracle for the set K={x∈R^n:f(x)≤f(x_0)} can be polynomially reduced to the comparison oracle of the function *f*. Combining these results with known results of D. Dadush et al., we give an algorithm with (O(n))^n*logR calls to the comparison oracle for checking the non-emptiness of the set K∩Z^n, where *K* is included to the Euclidean ball of a radius *R*. Additionally, we give a randomized algorithm with the expected oracle complexity (O(n))^n*logR for the problem to find an integral vector that minimizes values of *f* on an Euclidean ball of a radius *R*. It is known that the classes of convex, strictly quasiconvex functions, and quasiconvex polynomials are included into the class of conic functions. Since any system of conic functions can be represented by a single conic function, the last facts give us an opportunity to check the feasibility of any system of convex, strictly quasiconvex functions, and quasiconvex polynomials by an algorithm with (O(n))^n*logR calls to the comparison oracle of the functions. It is also possible to solve a constraint minimization problem with the considered classes of functions by a randomized algorithm with (O(n))^n*logR expected oracle calls.