Compilare: main.cpp: In function 'int main()': main.cpp:20:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<g[x].size() && j<g[y].size()){ ~^~~~~~~~~~~~ main.cpp:20:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<g[x].size() && j<g[y].size()){ ~^~~~~~~~~~~~ main.cpp: In function 'void read()': main.cpp:34:33: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &n, &m); ^ main.cpp:36:37: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &x, &y); ^