View Compilation Error

24490_0_20593.cpp:5: error: `main' must return `int'
24490_0_20593.cpp: In function `int main(...)':
24490_0_20593.cpp:9: error: `scanf' undeclared (first use this function)
24490_0_20593.cpp:9: error: (Each undeclared identifier is reported only once for each function it appears in.)
24490_0_20593.cpp:15: error: `printf' undeclared (first use this function)
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