字符统计

点击打开链接

#include<iostream> 
#include<string>
//#include<stdio.h>
using namespace std;
struct Elem{
	int c;
	int count;
};
void main(){
	Elem a[256];
	char input[256];
	for (int i = 0; i < 256; i++){
		a[i].c = i;
		a[i].count = 0;
	}
	gets_s(input);
	char *p = input;
	while (*p != '\0'){ //记录输入的字符，每个字符出现的个数
		if (*p >= 'a'&&*p <= 'z' || *p >= 'A'&&*p <= 'Z' || *p >= '0'&&*p <= '9' || *p == ' '){
			a[*p].count++;
			p++;
		}
	}
	Elem t;
	for (int i = 0; i < 255; i++){ //把次数多的放到前面，用结构体的话，不但交换了次数，连带c，既ASC码也交换了。
		for (int j = 0; j < 255 - i; j++){
			if (a[j].count < a[j + 1].count){
				t = a[j];
				a[j] = a[j + 1];
				a[j + 1] = t;
			}
		}
	}
	int i = 0;
	while (a[i].count != 0){
		cout << char(a[i].c) << " ";
		i++;
	}
	cout << endl;

	system("pause");
}