我的代码中有错误，未声明的标识符

Question

编译时提示错误

error: use of undeclared identifier 'isVowel'; did you mean 'islower'?

#include <iostream>

#include <cstring>

using namespace std;

int main() {

char word[50];

int num = 0;

cout << "Enter word: ";

cin.getline(word,50);

for(int i=0; word[i]; ++i){

if(isVowel(word[i]))

++num;

}

cout<<"The total number of vowels are "<<num<<endl;



}

bool isVowel(char c){

if(c=='a' || c=='A')

return true;

else if(c=='e' || c=='E')

return true;

else if(c=='i' || c=='I')

return true;

else if(c=='o' || c=='O')

return true;

else if(c=='u' || c=='U')

return true;

return false;

}

Answer 1

您需要在使用函数之前对其进行原型设计。否则编译器不知道它存在：

bool isVowel(char c); // A prototype of the function you will later call

int main () {
    //... Whatever code you're doing....


}

bool isVowel(char c) {
   // Actually implement it here.

}