View Compilation Error

0_0_10256863_14753.cpp: In function `int main()':
0_0_10256863_14753.cpp:15: error: `a' undeclared (first use this function)
0_0_10256863_14753.cpp:15: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_10256863_14753.cpp:17: error: `b' undeclared (first use this function)
0_0_10256863_14753.cpp:22: error: `pro' undeclared (first use this function)
0_0_10256863_14753.cpp:37: error: name lookup of `i' changed for new ISO `for' scoping
0_0_10256863_14753.cpp:26: error:   using obsolete binding at `i'