View Compilation Error

0_0_30253058_20050.cpp: In function 'int main()':
0_0_30253058_20050.cpp:38:114: error: 'struct Node' has no member named 'r0'
             dp[i] = ((( (a[i].s - a[i].r)*(sum[i-1] - sum[a[i].x-1]) + a[i].s * a[i].v)) % mod) * quick_pow(a[i].r0, mod-2) % mod;
                                                                                                                  ^