PROGRAMMING:String copy

Write a custom function to copy the contents of a string (no more than 80 characters) to another character array. Main function input a string of characters, copy to another array output.
```
#include
int str_ copy(char *d,char *s){
//Please enter your code here
}
int main(){
char pa[81];
char pb[81];
gets(pa);
str_ copy(pb,pa);
printf("%s",pb);
return 0;
}
```
###Input example:
```in
#include
```
###Output example:
```out
#include
```







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