cout<<'123'; 单引号什么错误

Answer 1

一般只有个警告： warning: multi-character character constant

Answer 2

单引号里面只能有一个字符

Answer 3

svg.append("path")
.datum(topojson.mesh(uk, uk.objects.subunits, function(a, b) { return a === b && a.id === "IRL"; }))
.attr("d", path)
.attr("class", "subunit-boundary IRL").