swift 2:
for(var i=m;i<n;i++){}
swift 3:
for i in m..<n {}
swift 2:
for(var i=n;i>m;i--){}
swift 3:
if(n > m){
for k in m ..< n {
i = m+n-k
...
}
} 原文链接：https://www.f2er.com/swift/322051.html
swift 2:
for(var i=m;i<n;i++){}
swift 3:
for i in m..<n {}
swift 2:
for(var i=n;i>m;i--){}
swift 3:
if(n > m){
for k in m ..< n {
i = m+n-k
...
}
} 原文链接：https://www.f2er.com/swift/322051.html