View Compilation Error

0_0_18280632_20538.cpp: In function 'int main()':
0_0_18280632_20538.cpp:46:30: error: 'dp' was not declared in this scope
    if(du[i]&1) cou++,du[i]=((dp[i]+1)>>1)&1;else du[i]=(du[i]>>1)&1;
                              ^