knapsack.cpp: In function 'int main()':
knapsack.cpp:9:33: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
9 | #define rep(i,x,n) for(int i=x;i<n;i++)
| ^
knapsack.cpp:10:18: note: in expansion of macro 'rep'
10 | #define FOR(i,n) rep(i,0,n)
| ^~~
knapsack.cpp:51:9: note: in expansion of macro 'FOR'
51 | FOR(j,a[i].size())
| ^~~
knapsack.cpp:53:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
53 | if(inx==a[i].size())
| ~~~^~~~~~~~~~~~~
knapsack.cpp: In function 'void SIO(std::string)':
knapsack.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
27 | freopen((name+".in").c_str(),"r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:28:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
28 | freopen((name+".out").c_str(),"w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~