C: Write a function to find a sub string in a given string and replace it with another string?

Question

Given a dictionary of strings and another string find out if the string is an exact match to some words in the dictionary or varies at most in only one place of some word of the dictionary?

Answer 1

void replaceAll(std::string& str, const std::string& from, const std::string& to) {
if(from.empty())
return;
size_t start_pos = 0;
while((start_pos = str.find(from, start_pos)) != std::string::npos) {
str.replace(start_pos, from.length(), to);
start_pos += to.length(); // In case 'to' contains 'from', like replacing 'x' with 'yx'
}
}