/in/foo.cc: In function 'int count_coloring(int, int, int)':
/in/foo.cc:15:69: error: 'accumulate' was not declared in this scope
             dp[i][j] = (accumulate(dp[i-1].begin(), dp[i-1].end(), 0) - dp[i-1][j]) % p;
                                                                     ^