View Compilation Error

0_0_7930233_28255.cpp: In function `int main()':
0_0_7930233_28255.cpp:7: error: `s' undeclared (first use this function)
0_0_7930233_28255.cpp:7: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_7930233_28255.cpp:10: error: `i' undeclared (first use this function)