https://pintia.cn/problem-sets/994805260223102976/problems/994805312417021952

#include <stdio.h>

int main(){
    int T, tcase=1;
    scanf("%d",&T);
    while(T--){
        long long a, b, c;
        scanf("%11d%11d%11d",&a,&b,&c);
        if(a+b>c){
            printf("Case #%d is true;",tcase++);
        }else{
            printf("Case #%d is true;",tcase++);
        }
    }

    return 0;
}

#include <stdio.h>

int main(int argc, char** argv){
    int s5={0};
    int sum[5]={0};
    float avg[5]={0};
    int i,j;
    
    //输入与算法 
    for(i=0;i<5;i++){
        printf("Student %d : 3 scoren",i+1);
        for(j=0;j<3;j++){
            scanf("%d",&si);
            sum[i]=sum[i]+si;
        }
        avg[i]=sum[i]/3.0;
    }
    
    //输出 
    printf("Result:n");
    for(i=0;i<5;i++){
        for(j=0;j<3;j++){
            printf("%dt",si);
        }
        printf("n");
    }
    
    printf("n");
    
    for(i=0;i<5;i++){
        printf("第%d位同学总分为%d分t平均分为%.2f分nn",i+1,sum[1],avg[i]);
    }
    
    return 0;
}

#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <windows.h>

int main(int argc, char** argv){
    char pwd[21]="";
    char ch;
    int i, j;
    system("cls");
    for(i=0;i<3;i++){
        printf("Please type password:n");
        j=0;
        while(j<20&&(ch=getch())!='r'){
            pwd[j++]=ch;
            putchar('*');
        }
        pwd[j]='0';
        if(strcmp(pwd,"123456")==0){
            system("cls");
            printf("Welcome!n");
            getch();
            break;
        }else
            printf("nPassword Error!n");
    }
    if(i>=3){
        printf("n你到底知不知道密码是啥？！n");
        exit(0);
    }
    
    return 0;
    
}

https://pintia.cn/problem-sets/994805260223102976/problems/994805325918486528

//任何正整数，偶数除二，奇数(3n+1)除二，最后一定在某处一定得n=1。
//输入不超过1000的正整数，求出需要几步得n=1。

#include <stdio.h>

int main(){
    int n, step=0;          //定义n与记步
    scanf("%d",&n);
    while(n!=1){            //当n不等于1时参与循环算法
        if(n%2==0) n=n/2;   //当n为偶数时
        else n=(3*n+1)/2;   //当n为奇数时
        step++;             //记步+1
    }
    printf("%dn",step);
    return 0;
}

#include <stdio.h>

main(){
    char c[15]={"Hello World!"};
    puts(c);
    
    int i;
    for(i=0;i<15;i++)
        printf("%c",c[i]);
    
    return 0;
}