顺序查找/二分查找/冒泡排序/打印金字塔/打印乘法表

顺序查找

#include<stdio.h>

int seqSearch(int arr[],int arrLen ,int val){
	int i;
	for(i=0;i<arrLen;i++){
		if(arr[i]==val){
			return i;
		}
	}
	return -1;
}

void main(){
	int arr[]={23,1,34,89,101};
	int arrLen = sizeof(arr)/sizeof(int);
	int index = seqSearch(arr,arrLen,101);
	if(index!=-1){
		printf("找到下标为%d",index);
	}
	else 
		printf("没有找到！");
	getchar();
}

对有序数组进行二分查找

#include <stdio.h>

int binarySearch(int arr[],int leftIndex,int rightIndex,int findVal){
	if (leftIndex > rightIndex)
		return -1;
	int midIndex = (leftIndex + rightIndex)/2;
	int midVal = arr[midIndex];
	if(midVal > findVal)
		binarySearch(arr,leftIndex,midIndex-1,findVal);
	else if(midVal < findVal)
		binarySearch(arr,midIndex-1,rightIndex,findVal);
	else 
		return midIndex;
}

void main(){
	int arr[] = {1,8,10,89,1000,1234};
	int arrLen = sizeof(arr)/sizeof(int);
	int index = binarySearch(arr,0,arrLen-1,1000);
	if(index != -1)
		printf("找到index = %d",index);
	else 
		printf("没找到");
	getchar();

}

嵌套循环求总分平均分

#include <stdio.h>
void main()
{
	int stuNum = 5;
	int classNum = 3;
	double classTotalScore = 0.0;
	double score = 0.0;
	int i,j;
	double AllclassTotalScore = 0.0;
	for(i=1;i<=classNum;i++){
		classTotalScore = 0.0;
		for(j=1;j<=stuNum;j++){
			printf("\n请输入第%d班级的第%d个学生的成绩 ",i,j);
			scanf("%lf",&score);
			classTotalScore += score;
		}
		AllclassTotalScore += classTotalScore;
		printf("\n 第%d个班级的平均分 = %.2f",i,classTotalScore/stuNum);
	}
	printf("\n 三个班级的总成绩为%.2f ",AllclassTotalScore);
	printf("\n 所有班级的平均分为 %.2f",AllclassTotalScore/(stuNum * classNum));
	getchar();
	getchar();
}

九九乘法表

#include <stdio.h>

void main(){
	int i,j;
	for(i=1;i<=9;i++){
		for(j=1;j<=i;j++)
		printf("%d * %d = %d   ",i,j,i*j);	
	printf("\n");
	}
	getchar();
}

打印实心金字塔

#include<stdio.h>

void main(){
	int i,j,k，TotalLevel;
	printf("请输入金字塔的层数");
	scanf("%d",&TotalLevel);
	for(i=1;i<=TotalLevel;i++){
		for(k=1;k<=TotalLevel-i;k++){//控制层数
			printf(" ");
		}
			for(j=1;j<=(i*2)-1;j++){//每行输出若干个*
			printf("*");
		}
		printf("\n");
	}
	getchar();
	getchar();
}

打印空心金字塔

	int i,j,k,TotalLevel;
	scanf("%d",&TotalLevel);
	for(i=1;i<=TotalLevel;i++){
		for(k=1;k<=TotalLevel-i;k++){//控制层数
			printf(" ");
		}
			for(j=1;j<=(i*2)-1;j++){//每行输出若干个*
				if(j==1||j==(i*2)-1||i==TotalLevel)//每行第一个和最后一个以及最后一层的全部输出*
					printf("*");
				else 
					printf(" ");
		}
		printf("\n");
	}
	getchar();
	getchar();
}

冒泡排序

#include<stdio.h>

void main(){
	int i,j,temp;
	int arr[]={98,45,100,20,40,55,78};
	int arrLen = sizeof(arr)/sizeof(int);
	for(i=0;i<arrLen-1;i++){
		for(j=0;j<arrLen-1;j++){
			if(arr[j]>arr[j+1]){
				temp = arr[j];
				arr[j] = arr[j+1];
				arr[j+1] = temp;
			}
		}
	}
	for(j=0;j<=arrLen-1;j++)
	printf("%d  ",arr[j]);
	getchar();
}