View Compilation Error

75010_0_28505.cpp: In function `void f(int, int)':
75010_0_28505.cpp:30: error: `find' undeclared (first use this function)
75010_0_28505.cpp:30: error: (Each undeclared identifier is reported only once for each function it appears in.)
75010_0_28505.cpp: In function `int main()':
75010_0_28505.cpp:56: error: `find' undeclared (first use this function)