计数c++字符串中出现的次数
Count number of occurrences in string c++?
我已经习惯了java,尽管知道c++的基本语法,但还是很纠结。我有一个函数,它试图计算字符串中出现的次数,但输出是一个tab有点奇怪。
下面是我的代码:#include <cstdlib>
#include <iostream>
#include <cstring>
/*
main
* Start
* prompt user to enter string
* call function
* stop
*
* count
* start
* loop chars
* count charts
* print result
* stop
*/
using namespace std;
void count(const char s[], int counts[]);
int main(int argc, char** argv) {
int counts[26];
char s[80];
//Enter a string of characters
cout << "Enter a string: "; // i.e. any phrase
cin.getline(s,80);
cout << "You entered " << s << endl;
count(s,counts);
//display the results
for (int i = 0; i < 26; i++)
if (counts[i] > 0)
cout << (char)(i + 'a') << ": " << counts[i] << "Times " << endl;
return 0;
}
void count(const char s[], int counts[]){
for (int i = 0; i < strlen(s); i++)
{
char c = tolower(s[i]);
if (isalpha(c))
counts[c - 'a']++;
}
}
输出如下:
输入字符串:Dylan
你输入了Dylan
b: 1Times
c: 1Times
d: 2Times
f: 1Times
h: 1Times
i: 1229148993Times
j: 73Times
l: 2Times
n: 2Times
p: 1Times
r: 1Times
v: 1Times
如果你能给我任何帮助,我将非常感激。虽然这是简单的东西,但我是一个java迷。_——您的counts
未初始化。您需要首先将所有元素设置为0。
您需要将计数向量归零。试一试counts[26]={0};
我不知道java,但是你必须在C/c++中初始化变量。下面是你的代码:
#include <cstdlib>
#include <iostream>
#include <cstring>
using namespace std;
void count(const char s[], int counts[]){
for (int i = 0; i < strlen(s); i++)
{
char c = tolower(s[i]);
if (isalpha(c))
counts[c - 'a']++;
}
}
int main(int argc, char** argv) {
int counts[26];
char s[80];
//Enter a string of characters
cout << "Enter a string: "; // i.e. any phrase
cin.getline(s,80);
for(int i=0; i<26; i++)
counts[i]=0;
cout << "You entered " << s << endl;
count(s,counts);
//display the results
for (int i = 0; i < 26; i++)
if (counts[i] > 0)
cout << (char)(i + 'a') << ": " << counts[i] << "Times " << endl;
return 0;
}