Compilare: main.cpp: In function 'int main()': main.cpp:40:19: warning: unused variable 'b' [-Wunused-variable] long long b = INF; ^ main.cpp:16:42: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d%d%d", &n, &m, &s, &f); ^ main.cpp:17:57: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i <= m; i++) fscanf(fi,"%lld", &c[i]); ^ main.cpp:20:30: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d", &x, &y); ^ main.cpp:30:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d", &x, &y); ^