View Compilation Error

0_0_16264567_5537.cpp: In function 'int main()':
0_0_16264567_5537.cpp:85:28: error: 'assert' was not declared in this scope
             assert(e[i].w>0);
                            ^
0_0_16264567_5537.cpp:106:29: error: 'assert' was not declared in this scope
                 assert(tot>0);
                             ^