0_0_20051149_10486.c: In function 'main':
0_0_20051149_10486.c:7:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
for(int n1 = 1; n1 < 30; ++n1)
^
0_0_20051149_10486.c:7:2: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_20051149_10486.c:9:3: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
for(int n2 = 1; n2 <= n1 + 1; ++n2)
^
0_0_20051149_10486.c:17:2: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
for(int n1 = 0; n1 < n; ++n1)
^
0_0_20051149_10486.c:19:3: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
for(int n2 = 1; n2 <= n1 + 1; ++n2)
^
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