Compilare: user.cpp: In function ‘void interschimba()’: user.cpp:63:43: warning: operation on ‘c[i]’ may be undefined [-Wsequence-point] a[i] = a[i] + c[i] - (c[i] = a[i]); ^ user.cpp:64:24: warning: operation on ‘m’ may be undefined [-Wsequence-point] k = k + m - (m = k); ^ user.cpp: In function ‘int main()’: user.cpp:102:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("largestroot.in", "r", stdin); ^ user.cpp:103:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("largestroot.out", "w", stdout); ^ user.cpp:105:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &T); ^ user.cpp:108:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &N); ^ user.cpp:111:25: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(sir[i]); ^ 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:111:25: /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); ^ /tmp/cczB0xjC.o: In function `main': user.cpp:(.text.startup+0xb7): warning: the `gets' function is dangerous and should not be used.