#include <bits/stdc++.h> static inline int64_t M = 9ull; extern std::pair<std::vector<int>, long long> transaction(long long M); static void buy_souvenirs(int N, long long P0) { std::vector<int32_t> bought(N, 0); for(int32_t type = 0; type < N; type++) { while(bought[type] < type) { for(int64_t M = 1; M < P0; M++) { auto transactions = transaction(M); auto& L = transactions.first; if(static_cast<int32_t>(L.size()) == 1 && L[0] == type) { bought[type]++; break; } } } } } int main() { buy_souvenirs(3, 4); }

/usr/bin/ld: /tmp/ccKWLbgF.o: in function `main':
stub.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccPOc7y9.o:souvenirs.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccKWLbgF.o: in function `main':
stub.cpp:(.text.startup+0x99): undefined reference to `buy_souvenirs(int, long long)'
collect2: error: ld returned 1 exit status