Language: C

#include<stdio.h>
int main(void) {
	double a, b;
	scanf("%f %f",&a,&b);
	if(a <= 35.5)
		if(b <= 71.0)
			printf("AAA\n");
		else
			if(b <= 77.0)
				printf("AA\n");
			else
				if(b <= 83.0)
					printf("A\n");
				else
					if(b <= 89.0)
						printf("B\n");
					else
						if(b <= 105.0);
							printf("C\n");
						else
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
	else
		if(a <= 37.5)
			if(b <= 77.0)
				printf("AA\n");
			else
				if(b <= 83.0)
					printf("A\n");
				else
					if(b <= 89.0)
						printf("B\n");
					else
						if(b <= 105.0);
							printf("C\n");
						else
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
		else
			if(a <= 40.0)
				if(b <= 83.0)
					printf("A\n");
				else
					if(b <= 89.0)
						printf("B\n");
					else
						if(b <= 105.0);
							printf("C\n");
						else
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
			else
				if(a <= 43.0)
					if(b <= 89.0)
						printf("B\n");
					else
						if(b <= 105.0);
							printf("C\n");
						else
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
				else
					if(a <= 50.0)
						if(b <= 105.0);
							printf("C\n");
						else
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
					else
						if(a <= 55.0)
							if(b <= 116.0)
								printf("D\n")
							else
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
						else
							if(a <= 70.0)
								if(b <= 148.0)
									printf("E\n");
								else
									printf("NA\n");
							else
								printf("NA\n");
	return 0;
}

Compiler output:
main.c: In function 'main':
main.c:20:49: error: 'else' without a previous 'if'
   20 |                                                 else
      |                                                 ^~~~
main.c:22:78: error: expected ';' before 'else'
   22 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   23 |                                                         else
      |                                                         ~~~~                  
main.c:28:9: error: 'else' without a previous 'if'
   28 |         else
      |         ^~~~
main.c:41:49: error: 'else' without a previous 'if'
   41 |                                                 else
      |                                                 ^~~~
main.c:43:78: error: expected ';' before 'else'
   43 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   44 |                                                         else
      |                                                         ~~~~                  
main.c:49:17: error: 'else' without a previous 'if'
   49 |                 else
      |                 ^~~~
main.c:59:49: error: 'else' without a previous 'if'
   59 |                                                 else
      |                                                 ^~~~
main.c:61:78: error: expected ';' before 'else'
   61 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   62 |                                                         else
      |                                                         ~~~~                  
main.c:67:25: error: 'else' without a previous 'if'
   67 |                         else
      |                         ^~~~
main.c:74:49: error: 'else' without a previous 'if'
   74 |                                                 else
      |                                                 ^~~~
main.c:76:78: error: expected ';' before 'else'
   76 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   77 |                                                         else
      |                                                         ~~~~                  
main.c:82:33: error: 'else' without a previous 'if'
   82 |                                 else
      |                                 ^~~~
main.c:86:49: error: 'else' without a previous 'if'
   86 |                                                 else
      |                                                 ^~~~
main.c:88:78: error: expected ';' before 'else'
   88 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   89 |                                                         else
      |                                                         ~~~~                  
main.c:94:41: error: 'else' without a previous 'if'
   94 |                                         else
      |                                         ^~~~
main.c:97:78: error: expected ';' before 'else'
   97 |                                                                 printf("D\n")
      |                                                                              ^
      |                                                                              ;
   98 |                                                         else
      |                                                         ~~~~