定义一个结构体变量(包括年,月,日),计算该日在本年中是第几天(规定一月一日为第一天)。(10分)
#include<stdlib.h> #include<stdio.h> #include<iostream> using namespace std; int main() { int a, b, c; double decide, x1, x2, m, n; cout << "求一元二次方程的解" << endl << "请输入系数a,b,c(用空格隔开)"<<endl; cin >> a >> b >> c; decide = (double)b * (double)b - 4 * (double)a * (double)c; if (decide < 0) { printf("当前方程无解 \n"); } else if (decide < 0) { m = -b / (2 * a); n = sqrt(decide) / (2 * (double)a); x1 = m + n; cout << "当前一元二次方程有两个相同的解" << x1; } else if(decide >0) { m = -b / (2 * a); n = sqrt(decide) / (2 * (double)a); x1 = m + n; x2 = m - n; printf("一元二次方程的解是:\nx1=%.2f\nx2=%.2f\n", x1, x2); system("pause"); } return 0; }
#include<iostream> #include<stdlib.h> #include<stdio.h> using namespace std; int main() { int b; cout << "请输入口令\n"; while (1) { cin >> b; if (b == 456) { break; } else { cout << "输入错误,请再来一次\n"; } } system("color 02"); cout << "输入正确"; }
#include<iostream> #include<stdlib.h> #include<stdio.h> using namespace std; int main() { cout << "这个程序将输出000-9999之间能对3整除的回文数"; int a, i = 0; for(a=1000;a<10000;a++) { if(a/1000==a/1%10 && a/100%10==a/10%10 && a%3==0) { cout << i; printf("%5d\n", a); i++; } } }
#include<stdlib.h> #include<stdio.h> #include<iostream> using namespace std; float chufa(int n) { float sum ; sum = 1.0; int m=0; for (int i = 1; i <= n; i++) { m = m + i; } sum = sum / m; return sum; } int main() { int m,s=1; float summary=0; cin >> m; for (s; s <= m; s++) { summary = chufa(s)+summary; } cout << summary; return 0; }
#include<iostream> #include<stdio.h> #include<cmath> using namespace std; /*定义一个结构体变量(包括年,月,日),计算该日在本年中是第几天(规定一月一日为第一天)。(10分)*/ struct book { int year=2019; int month; int day; }; int main() { struct book a; int n; cout << "请输入月和日" << endl; cin >> a.month >> a.day; if (a.month < 0 || a.month>12) { cout << "月份输入错误\n"; } if (a.day < 0 || a.day>31) { cout << "日子输入错误\n"; } if (a.month > 0 && a.month < 13 && a.day>0 && a.day < 30) { n = a.day + 30 * a.month; cout << "这是一年中的第" << n << "天" << endl; } else { cout << "数据输入有误,请再次输入"; } return 0; }
#include<stdlib.h> #include<string.h> #include<stdio.h> #include<iostream> using namespace std; int main(void) { int s,a,b,c,m,n,sum; const char r[10][30] = { "ling","yi","er","san","si","wu","liu","qi","ba","jiu" }; cout << "请输入一个小于100的正整数"<<endl; cin >> s; if (s > 0 && s < 100) { a=s/10; b = s % 10; sum = a + b; m = sum / 10; n = sum % 10; cout << r[m] <<" "<<r[n]; } else { cout << "请输入正确的数字"; } return 0; }
#include<iostream> #include<stdlib.h> #include<stdio.h> using namespace std; void swap_s(int * pa, int* pb) { int t = *pa; * pa = *pb; * pb = t; } int main() { int a , b ; int a1, b1; cout << "此程序将a 和 b的值进行交换,<<endl<<先输出交换前的值,再输出交换后的值"<<endl; cout << "请输入a b(用空格隔开)"<<endl; cin >> a >> b; a1 = a; b1 = b; swap_s(&a, &b); cout << a1 << " " << b1 << endl; cout << a <<" "<< b<<endl; return 0; }
#include<stdlib.h> #include<stdio.h> #include<iostream> using namespace std; void fun() { int a[10]; cout << "请输入10个整数(用空格隔开)" << endl; for (int u = 0; u <= 9; u++) { cin >> a[u]; } int i, j; int temp; cout << "从小到大排序"<<endl; int n = 10; for (i = 0; i < n;i++) { for (j = n - 1; j > i; j--)//第一次循环是针对于a[9]的排序,以此类推 { if (a[j - 1] < a[j]) { temp = a[j - 1]; a[j - 1] = a[j]; a[j] = temp; } } } for (int w = 9; w >= 0; w--) { cout << a[w]<<endl; } } int main(void) { fun(); return 0; }
#include<stdlib.h> #include<stdio.h> #include<iostream> using namespace std; //void fun(char *a) void fun(char a[100]) { int m, i; for (m = 0; m < 50; m++) { if (a[m] == ‘\0‘) { cout << "字符串的长度为:" << m + 1 << endl; break; } } for (i = m - 1; i >= 0; i--) { cout << a[i]; } } int main() { char a[50]; cout << "请输入字符串"<<endl; cin >> a; fun(a); return 0; }
#include<iostream> #include<cmath> #include<stdio.h> using namespace std; int main() { int i, m = 2, n = 1, t; double s = 0.0; for (i = 1; i <= 20; i++) { s = s + (m * 1.0 / n); t = m+n; n = m; m = t; } printf("前20项之和为:%.2lf", s); return 0; }
原文:https://www.cnblogs.com/Loving-Q/p/11991249.html