Compilare: main.cpp: In function 'int main()': main.cpp:32:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0; i < g[z].size(); i++ ) { ~~^~~~~~~~~~~~~ main.cpp:50:37: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=] fprintf( fout, "%d\n", v.size() ); ^ main.cpp:52:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0; i < v.size(); i++ ) ~~^~~~~~~~~~ main.cpp:15:46: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d%d%d%d", &n, &m, &x, &y ); ^ main.cpp:17:38: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d%d", &a, &b ); ^