View Compilation Error

0_0_31361933_22114.cpp: In function 'int main()':
0_0_31361933_22114.cpp:25:34: error: expected primary-expression before '<' token
     freopen("2037.in","r",stdin);<span style="white-space:pre"> </span>//这个记得删。。。
                                  ^
0_0_31361933_22114.cpp:25:35: error: 'span' was not declared in this scope
     freopen("2037.in","r",stdin);<span style="white-space:pre"> </span>//这个记得删。。。
                                   ^
0_0_31361933_22114.cpp:28:23: error: 'n' was not declared in this scope
     while(scanf("%d",&n)!=EOF)
                       ^
0_0_31361933_22114.cpp:32:13: error: 'i' was not declared in this scope
         for(i=0;i<n;i++)
             ^
0_0_31361933_22114.cpp:41:9: error: 'maxn' was not declared in this scope
         maxn=1;
         ^
0_0_31361933_22114.cpp:42:13: error: 'i' was not declared in this scope
         for(i=1;i<n;i++)
             ^
0_0_31361933_22114.cpp:44:17: error: 'j' was not declared in this scope
             for(j=0;j<i;j++)
                 ^