实验3

include <stdio.h>

char score_to_grade(int score);
int main() {
int score;
char grade;
while(scanf("%d", &score) != EOF) {
grade = score_to_grade(score);
printf("分数: %d, 等级: %c\n\n", score, grade);
}
return 0;
}
char score_to_grade(int score) {
char ans;
switch(score/10) {
case 10:
case 9: ans = 'A'; break;
case 8: ans = 'B'; break;
case 7: ans = 'C'; break;
case 6: ans = 'D'; break;
default: ans = 'E';
}
return ans;
}

include <stdio.h>

int sum_digits(int n);
int main() {
int n;
int ans;
while(printf("Enter n: "), scanf("%d", &n) != EOF) {
ans = sum_digits(n);
printf("n = %d, ans = %d\n\n", n, ans);
}
return 0;
}
int sum_digits(int n) {
int ans = 0;
while(n != 0) {
ans += n % 10;
n /= 10;
}
return ans;
}

#include <stdio.h>
int power(int x, int n);
int main() {
int x, n;
int ans;
while(printf("Enter x and n: "), scanf("%d%d", &x, &n) != EOF) {
ans = power(x, n);
printf("n = %d, ans = %d\n\n", n, ans);
}
return 0;
}
int power(int x, int n) {
int t;
if(n == 0)
return 1;
else if(n % 2)
return x * power(x, n-1);
else {
t = power(x, n/2);
return t*t;
}

include <stdio.h>

// 题目要求的函数原型
int classify_triangle(int a, int b, int c);

int main() {
int a, b, c;
int res;
while(printf("请输入三角形三边: "), scanf("%d%d%d", &a, &b, &c) != EOF) {
res = classify_triangle(a, b, c);
switch(res) {
case 0: printf("不能构成三角形\n"); break;
case 1: printf("普通三角形\n"); break;
case 2: printf("等边三角形\n"); break;
case 3: printf("等腰三角形\n"); break;
case 4: printf("直角三角形\n"); break;
}
printf("\n");
}
return 0;
}
int classify_triangle(int a, int b, int c) {
if(a + b <= c || a + c <= b || b + c <= a || a <=0 || b <=0 || c <=0) {
return 0;
}
if(a == b && b == c) {
return 2;
}
if(aa + bb == cc || aa + cc == bb || bb + cc == a*a) {
return 4;
}
if(a == b || a == c || b == c) {
return 3;
}
return 1;
}

include <stdio.h>

int func(int n, int m);
int main() {
int n, m;
int ans;
while(scanf("%d%d", &n, &m) != EOF) {
ans = func(n, m);
printf("n = %d, m = %d, ans = %d\n\n", n, m, ans);
}
return 0;
}
int func(int n, int m){
if(m == 0||m == n||m > n)return 1;
return func(n-1,m) + func(n-1,m-1);
}

include <stdio.h>

include <stdlib.h>

void print_charman(int n);

int main() {
int n;
printf("Enter n: ");
scanf("%d", &n);
print_charman(n);
return 0;
}
void print_charman(int n) {
for(int i = n; i >= 1; i--) {
for(int j = 1; j <= i; j++) {
printf(" O");
}
printf("\n");
for(int j = 1; j <= i; j++) {
printf("");
}
printf("\n");
for(int j = 1; j <= i; j++) {
printf(" II");
}
printf("\n");
}
}