Thread: Need help with a loop!

I wrote this code and it all works great, but as you'll notice at the end, I need to prompt the user to enter Y or N. If they enter N, then the program ends, I can do that. But if the user enter Y, the program need to ask for the info to be typed in again. How can I do this?

I'm not asking you guys to write it for me, just help me get started with that.

Code:

#include <stdio.h>

char first, last, GetLetterGrade, x;
float test_one, test_two, test_three;
float test_one_score, test_two_score, test_three_score;
float averageGrade;

int main()
{
    //Get the maximum scores.
    printf("Please enter the maximum score possible for test one: ");
    scanf("%f", &test_one);

    printf("Please enter the maximum score possible for test two: ");
    scanf("%f", &test_two);

    printf("Please enter the maximum score possible for test three: ");
    scanf("%f", &test_three);


    //Get students name.
    printf("\nEnter your first and last name initials: ");
    scanf(" %c%c", &first, &last);


    //Get student test grades  Checks for proper input.
    printf("\n\nEnter your test one score: ");
    scanf("%f", &test_one_score);
    if(test_one_score < 0 || test_one_score > test_one){
        printf("\nInvalid score, the valid range is : 0-%.2f\nEnter correct score:", test_one);
        scanf("%f", &test_one_score);
    }

    printf("Enter your test two score: ");
    scanf("%f", &test_two_score);
    if(test_one_score < 0 || test_two_score > test_two){
        printf("\nInvalid score the valid range is : 0-%.2f\nEnter correct score:", test_two);
        scanf("%f", &test_two_score);
    }

    printf("Enter your test three score: ");
    scanf("%f", &test_three_score);
    if(test_one_score < 0 || test_three_score > test_three){
        printf("\nInvalid score, the valid range is : 0-%.2f\nEnter correct score:", test_three);
        scanf("%f", &test_three_score);
    }



    //Calculate average grade.
    averageGrade = (test_one_score + test_two_score + test_three_score)/(test_one + test_two + test_three) * 100;


    //Output student's info.
    printf("\nStudent's initials: %c%c", first, last);
    printf("\nAverage Score: %.2f", averageGrade);

    //Output letter grade.
    if(averageGrade >= 90){
        printf("\nLetter grade: A");
    }
    else if((averageGrade >= 80) && (averageGrade < 90)){
        printf("\nLetter grade: B");
    }
    else if((averageGrade >= 70) && (averageGrade < 80)){
        printf("\nLetter grade: C");
    }
    else if((averageGrade >= 60) && (averageGrade < 70)){
        printf("\nLetter grade: D");
    }
    else if(averageGrade < 60){
        printf("\nLetter grade: F");
    }


    //Another student.
    printf("\n\nCalculate another student grade (Enter Y for Yes, N for No): ");
    scanf(" %c", &x);




    return 0;
}

What kind of a loop should I use?

Thanks, that helped clear some things up for me.

I ended up using an if else statement:

Code:

printf("\n\nCalculate another student grade (Enter Y for Yes, N for No): ");
scanf(" %c", &x);
if( x == 'N' || x == 'n'){
   return 0;
}
else if(x == 'Y' || x == 'y'){
   return main();
}

When they say no, the program ends, but when they say yes, the whole program starts again. Can you suggest how I can make it so that instead of starting the whole program again, it will just go back to a certain part?

Try this:

Code:

int c;    
int i = 0;
// You may need this.
    SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), 0); 

    
do{
        printf("Now processing number %u\n", ++i);
        
//////////////////
        
// Your code here.
        
/////////////////////
        puts("Another? y = yes, n = no");
        c = getchar();
    }
while(toupper(c) != 'N');