Compilare: user.cpp: In function ‘int main()’: user.cpp:34:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=1;j<g[i].size();j++) sum[j]=sum[j-1]+g[i][j]; ^ user.cpp:38:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0;k<g[i].size();k++) { ^ user.cpp:15:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ruksak.in","r",stdin); ^ user.cpp:16:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ruksak.out","w",stdout); ^ user.cpp:18:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:21:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^