View Compilation Error

0_0_33689276_22133.cpp: In function 'void copy(int, int)':
0_0_33689276_22133.cpp:22:22: error: 'sum' was not declared in this scope
     val[x] = val[y], sum[x] = sum[y], siz[x] = siz[y];
                      ^
0_0_33689276_22133.cpp: In function 'void pushup(int)':
0_0_33689276_22133.cpp:27:5: error: 'sum' was not declared in this scope
     sum[x] = sum[ch[x][0]] + sum[ch[x][1]] + val[x];
     ^
0_0_33689276_22133.cpp: In function 'int New(int)':
0_0_33689276_22133.cpp:34:74: error: 'sum' was not declared in this scope
     e[++Size] = gg, siz[gg] = 1, val[gg] = x, ch[gg][0] = ch[gg][1] = 0, sum[gg] = x;
                                                                          ^
0_0_33689276_22133.cpp: In function 'long long int query(int, int)':
0_0_33689276_22133.cpp:139:54: error: 'sum' was not declared in this scope
     split(rt, a, c, R), split(a, a, b, L - 1), ans = sum[b], merge(a, a, b), merge(rt, a, c);
                                                      ^