优秀是一种习惯

截一个游戏结束时的图如下：

目前该函数已被fun包收录：

install.packages(“fun”, repos=”http://R-Forge.R-project.org”)

代码如下：

function (size = NULL, bg = "lightblue", z = NULL, ...)
{
    if (!is.null(size)) {
        n <- size[1]
        m <- size[2]
    }
    if (!is.null(z)) {
        n <- dim(z)[1]
        m <- dim(z)[2]
        if (!is.null(size))
            warning("Because \"z\" is specialized, parameter \"size\" will be omitted.")
    }
    z.right <- matrix(1:(n * m), n, byrow = TRUE)
    z.right[n, m] <- 0
    neg_seq.length <- function(x) {
        len <- 0
        for (i in 1:(length(x) - 1)) {
            tmp <- x[(i + 1):length(x)] - x[i]
            len <- len + sum(tmp < 0)
        }
    }
    len.right <- neg_seq.length(as.vector(z.right)) + n + m
    if (is.null(z))
        z <- matrix(sample(0:(n * m - 1)), n)
    else {
        len.z <- neg_seq.length(as.vector(z)) + sum(which(z ==
            0, arr.ind = TRUE))
        if ((len.right%%2) != (len.z%%2))
            stop("The sliding puzzle is insoluble!")
    }
    len.z <- neg_seq.length(as.vector(z)) + sum(which(z == 0,
        arr.ind = TRUE))
    while ((len.right%%2) != (len.z%%2) | all(z == z.right)) {
        z <- matrix(sample(0:(n * m - 1)), n)
        len.z <- neg_seq.length(as.vector(z)) + sum(which(z ==
            0, arr.ind = TRUE))
    }
    z[!z] <- NA
    replot <- function(z) {
        bg <- ifelse(z, bg, "white")
        fg <- ifelse(z, bg, "white")
        par(mar = c(0, 0, 0, 0), bg = "white")
        plot(c(0, m), c(0, n), type = "n", axes = FALSE, asp = 1,
            xlab = "", ylab = "")
        segments(0:m, rep(0, m + 1), 0:m, rep(n, m + 1), col = "grey",
            lwd = 2)
        segments(rep(0, n + 1), 0:n, rep(m, n + 1), 0:n, col = "grey",
            lwd = 2)
        symbols(0.5 + rep(0:(m - 1), each = n), 0.5 + rep((n -
            1):0, m), squares = rep(0.9, n * m), add = TRUE,
            inches = FALSE, fg = as.vector(fg), bg = as.vector(bg))
        text(0.5 + rep(0:(m - 1), each = n), 0.5 + rep((n - 1):0,
            m), as.vector(z), cex = 3)
    }
    push <- function(x, begin, space) {
        tmp <- x[space]
        if (begin < space) {
            x[(begin + 1):space] <- x[begin:(space - 1)]
            x[begin] <- tmp
        }
        if (begin > space) {
            x[(begin - 1):space] <- x[begin:(space + 1)]
            x[begin] <- tmp
        }
        x
    }
    count <- 0
    mousedown <- function(buttons, x, y) {
        plx <- grconvertX(x, "ndc", "user")
        ply <- grconvertY(y, "ndc", "user")
        m.col <- ceiling(plx)
        m.row <- n - floor(ply)
        ind.NA <- which(is.na(z), arr.ind = TRUE)
        if (!xor(m.row == ind.NA[1], m.col == ind.NA[2]))
            cat("Warning: Cannot push any number!\n")
        ind.NA <- which(is.na(z), arr.ind = TRUE)
        if (ind.NA[1] == m.row & ind.NA[2] != m.col) {
            z[m.row, ] <<- push(z[m.row, ], m.col, ind.NA[2])
            cat("step = ", count <<- count + 1, "\n")
        }
        if (ind.NA[1] != m.row & ind.NA[2] == m.col) {
            z[, m.col] <<- push(z[, m.col], m.row, ind.NA[1])
            cat("step = ", count <<- count + 1, "\n")
        }
        replot(z)
        flag <- z == z.right
        if (all(flag[!is.na(flag)])) {
            paste("You win! Time:", round((proc.time() - ptm)[3],
                2), "seconds.")
        }
    }
    ptm <- proc.time()
    windows(5, 5)
    replot(z)
    if (.Platform$OS.type == "windows")
        getGraphicsEvent("Game begin!", onMouseDown = mousedown)
}