0_0_39480555_989.cpp: In function 'void solve()': 0_0_39480555_989.cpp:55:13: error: 'i' was not declared in this scope 55 | pre(i,1,n) | ^ 0_0_39480555_989.cpp:55:9: error: 'pre' was not declared in this scope 55 | pre(i,1,n) | ^~~