View Compilation Error

0_0_21938972_28354.cpp:4:11: error: '::main' must return 'int'
 void main()
           ^
0_0_21938972_28354.cpp: In function 'int main()':
0_0_21938972_28354.cpp:21:23: error: 'strcmp' was not declared in this scope
    if(strcmp(t[i],t[j])==0)
                       ^