Compilare: main.cpp: In function 'void exp2(int, int)': main.cpp:49:15: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if( xx>=1 && yy>=1 && xx<=N && yy<=M) ^ main.cpp: In function 'int main()': main.cpp:93:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pirati.in","r",stdin); ^ main.cpp:94:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pirati.out","w",stdout); ^ main.cpp:95:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n",&N,&M,&QQ); ^ main.cpp:96:47: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=N;++i) fgets(a[i]+1,Nmax,stdin); ^ main.cpp:116:42: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x1,&y1,&x2,&y2); ^