View Compilation Error

0_0_24301261_4688.cpp: In function 'void solve1()':
0_0_24301261_4688.cpp:15:22: error: 'strcmp' was not declared in this scope
   if(!strcmp(str,"IN")){
                      ^
0_0_24301261_4688.cpp: In function 'void solve2()':
0_0_24301261_4688.cpp:35:22: error: 'strcmp' was not declared in this scope
   if(!strcmp(str,"IN")){
                      ^
0_0_24301261_4688.cpp: In function 'int main()':
0_0_24301261_4688.cpp:56:24: error: 'strcmp' was not declared in this scope
   if(!strcmp(str,"FIFO")){
                        ^