View Compilation Error

0_0_29613449_30324.cpp:1:1: error: 'https' does not name a type
 https://www.cnblogs.com/dirge/p/6039389.html
 ^
0_0_29613449_30324.cpp:3:1: error: expected unqualified-id before 'if'
 if(n<m) swap(n,m);
 ^
0_0_29613449_30324.cpp:4:1: error: 'n' does not name a type
 n=(int)(k*(n-m));
 ^
0_0_29613449_30324.cpp:5:1: error: expected unqualified-id before 'if'
 if(n==m) printf("后手胜\n");
 ^
0_0_29613449_30324.cpp:6:1: error: expected unqualified-id before 'else'
 else printf("先手胜\n");
 ^