Compilare: user.cpp: In function ‘int main()’: user.cpp:23:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] dp[l[i]+1][p]=l[i]+1; ^ user.cpp:27:35: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(a[i][j]==p) dp[j][p]=j; ^ user.cpp:28:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] else dp[j][p]=dp[j+1][p]; ^ user.cpp:28:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] else dp[j][p]=dp[j+1][p]; ^ user.cpp:39:43: warning: array subscript has type ‘char’ [-Wchar-subscripts] else pr[j]=dp[pr[j-1]+1][op[j]]; ^ user.cpp:8:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("search.in","r",stdin); ^ user.cpp:9:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("search.out","w",stdout); ^ user.cpp:10:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:11:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&m); ^ user.cpp:14:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a[i]+1); ^ user.cpp:17:12: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^ user.cpp:19:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c\n",&op[i]); ^ user.cpp:23:29: warning: iteration 3u invokes undefined behavior [-Waggressive-loop-optimizations] dp[l[i]+1][p]=l[i]+1; ^ user.cpp:22:5: note: containing loop for(p='a';p<='z';p++) ^ In file included from /usr/include/stdio.h:934:0, from /usr/include/c++/4.8/cstdio:42, from user.cpp:1: In function ‘char* gets(char*)’, inlined from ‘int main()’ at user.cpp:14:17: /usr/include/i386-linux-gnu/bits/stdio2.h:230:28: warning: call to ‘__gets_warn’ declared with attribute warning: please use fgets or getline instead, gets can't specify buffer size [enabled by default] return __gets_warn (__str);