`solvechart` <- function(x, ...) {

    dots <- list(...)

    if (all(rowSums(x) > 0)) {

        PIlayers <- attr(x, "PIlayers")

        # number of:
        PIs <- ncol(x)
        poc <- nrow(x) # positive observed configurations (minterms)

        # sink("timings.txt", append = TRUE)
        # cat(sprintf("Minterms: %s, PIs: %s", poc, PIs))
        # sink()

        model <- list(
            A = x,
            modelsense = "min",
            rhs = rep(1, poc),
            sense = rep(">=", poc),
            vtype = rep("B", PIs)
        )

        if (!is.null(PIlayers)) {
            PIlayers <- PIlayers[PIlayers > 0]
        }

        if (length(PIlayers) < 2 || isFALSE(dots$multiobj)) {
            model$obj <- rep(1, PIs)
        } else {
            # cat(paste(PIlayers, collapse = " "))

            for (i in seq(length(PIlayers), 2)) {
                PIlayers[i] <- PIlayers[i] - PIlayers[i - 1]
            }

            # cat(" -- ",  paste(PIlayers, collapse = " "), "\n")

            value <- rep(
                rev(2^seq(0, length(PIlayers) - 1)),
                PIlayers
            )

            if (length(value) < PIs) {
                value <- c(value, rep(tail(value, n = 1), PIs - length(value)))
            } else if (PIs < length(value)) {
                value <- value[seq(PIs)]
            }

            # admisc::export(
            #     as.data.frame(t(x)),
            #     file = paste("pic", sample(5000, 1), ".csv", sep = ""),
            #     col.names = FALSE
            # )

            # admisc::export(
            #     as.data.frame(t(attr(x, "implicants"))),
            #     file = paste("imp", sample(5000, 1), ".csv", sep = ""),
            #     col.names = FALSE
            # )

            model$multiobj <- list(
                list(
                    objn = rep(1, PIs),
                    priority = 1,
                    weight = 1
                ),
                list(
                    objn = -1 * value,
                    priority = 0,
                    weight = 1
                )
            )
        }

        tc <- admisc::tryCatchWEM(
            solution <- gurobi::gurobi(
                model,
                params = list(
                    OutputFlag = 0,
                    LogToConsole = 0
                )
            )
        )

        if (is.null(tc$error)) {
            # sink("timings.txt", append = TRUE)
            # cat(sprintf(", Time: %s\n", round(solution$runtime, 3)))
            # sink()

            if (round(solution$objval[1]) < solution$objval[1]) {
                # the weighted method did not yield precise results
                temp <- sapply(solution$pool, function(x) {
                    return(round(x$objval[1]) == x$objval[1])
                })

                if (any(temp)) {
                    solution <- solution$pool[[which(temp)[1]]]$xn
                } else {
                    # There is still no ideintified solution with an integer number of PIs
                    # Give up weigthing
                    model$multiobj <- NULL

                    # and return the uneighted solution
                    model$obj <- rep(1, PIs)
                    solution <- gurobi::gurobi(
                        model,
                        params = list(
                            OutputFlag = 0,
                            LogToConsole = 0
                        )
                    )$x
                }
            } else {
                solution <- solution$x
            }
        } else {
            solution <- lpSolve::lp(
                "min",
                rep(1, ncol(x)),
                x,
                ">=",
                1,
                int.vec = seq(nrow(x)),
                all.bin = TRUE
            )$solution
        }

        return(as.integer(which(solution > 0)))
    }
}