View Compilation Error

0_0_33929463_27084.cpp:19:20: error: 'u' was not declared in this scope
 int dp[MAXN], tval[u], sz[MAXN];
                    ^
0_0_33929463_27084.cpp: In function 'int check(int, int, int)':
0_0_33929463_27084.cpp:23:16: error: 'tval' was not declared in this scope
         return tval[u];
                ^
0_0_33929463_27084.cpp: In function 'void insert(int&, int, int)':
0_0_33929463_27084.cpp:51:17: error: 'tval' was not declared in this scope
         dp[u] = tval[u] = x;
                 ^
0_0_33929463_27084.cpp: In function 'int Merge(int, int, int)':
0_0_33929463_27084.cpp:68:21: error: 'tval' was not declared in this scope
             dp[u] = tval[u];
                     ^