By the C, by the C, by the Beatutiful C

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Getting Started Programming in C

#include <math.h>
#include <stdio.h>

int main(void) {
  // statements end in a semicolon(;)
  printf("Hello World\n");
  printf("sqrt(4) is %f\n", sqrt(4));
}

Hello World
sqrt(4) is 2.000000