0_0_37855048_22871.cpp: In function 'int main()': 0_0_37855048_22871.cpp:59:17: error: 'S' was not declared in this scope S.insert(a[p]); ^ 0_0_37855048_22871.cpp:65:25: error: 'S' was not declared in this scope auto it=S.lower_bound(k); ^