#include <iostream>
char *strcat(
char *strDestination,
const char *strSource
) {
while(*strDestination) { strDestination++; }
while(*strDestination++ = *strSource++);
return strDestination;
}
int main() {
char src[] = "world";
char dest[500] = "hello";
strcat(dest, src);
std::cout << dest;
}
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