View Compilation Error

0_0_25066741_30844.cpp: In function 'int main()':
0_0_25066741_30844.cpp:22:17: error: 'x' was not declared in this scope
      t1+=son[j][x],dp[j][x]=max(dp[j][x],t1);
                 ^
0_0_25066741_30844.cpp:25:17: error: 'x' was not declared in this scope
      t2+=son[j][x],dp[j][x]=max(dp[j][x],t2);
                 ^