我来贴一些排名较高的答案，真的要膜拜啊：
1：
snail = function(array) {
var result;
while (array.length) {
// Steal the first row.
result = (result ? result.concat(array.shift()) : array.shift());
// Steal the right items.
for (var i = 0; i < array.length; i++)
result.push(array[i].pop());
// Steal the bottom row.
result = result.concat((array.pop() || []).reverse());
// Steal the left items.
for (var i = array.length - 1; i >= 0; i--)
result.push(array[i].shift());
}
return result;
}
2：
snail = function(array) {
var res = [];
while(array.length) {
res = res.concat(array.shift())
array = expand(array);
}
return res;
}
function expand(matrix){
return matrix.reduce(function(res, arr, i){
arr.forEach(function(n, j){
if (!res[j]) res[j] = [];
res[j][i] = n;
})
return res;
}, []).reverse();
}
3：
snail = function(array) {
var maxx = array[0].length,
maxy = maxx,
minx = -1, miny = 0,
x = 0, y = 0,
result = [], dir = "r";
for(var i = maxx*maxx;i>0;i--){
result.push(array[y][x]);
switch (dir){
case "u": y--; break;
case "l": x--; break;
case "d": y++; break;
case "r": x++; break;
}
if(x==maxx-1 && y==miny){ dir="d"; minx++; }
else if(x==maxx-1 && y==maxy-1){ dir="l"; miny++; }
else if(x==minx && y==maxy-1){ dir="u"; maxx--; }
else if(x==minx && y==miny){ dir="r"; maxy--; }
}
return result;
}
